Abstract:
A system, method and computer program product are provided for uninstalling software on a computer. In use, a plurality of software products identified on a computer is displayed. Further, a first user instruction to uninstall at least a portion of at least one of the software products from the computer is received. Such first user instruction is received via an interface. Still yet, the at least a portion of the at least one software product is uninstalled from the computer, in response to the receipt of the first user instruction. Also, a second user instruction may be received to cancel the uninstallation. Thus, the uninstallation may be cancelled, in response to the receipt of the second user instruction.

Description:
RELATED APPLICATION(S) 
     This is a continuation application of copending prior application Ser. No. 11/198,726 filed Aug. 4, 2005, which, in turn, is a continuation of application Ser. No. 10/456,208 filed Jun. 5, 2003, now issued under U.S. Pat. No. 7,107,366, which, in turn, is a continuation of application Ser. No. 10/264,670 filed Oct. 4, 2002, now issued under U.S. Pat. No. 6,668,289, which, in turn, is a continuation of application Ser. No. 10/136,266 filed Apr. 30, 2002, now issued under U.S. Pat. No. 6,496,875, which, in turn, is a continuation of application Ser. No. 09/661,117 filed Sep. 13, 2000, now issued under U.S. Pat. No. 6,457,076, which, in turn, is a continuation of application Ser. No. 08/660,488 filed Jun. 7, 1996, now issued under U.S. Pat. No. 6,151,643, the disclosure of which is incorporated herein by reference. 
    
    
     BACKGROUND 
     1. Field of Invention 
     The present invention relates to systems and methods for computer-based customer support, and more particularly, to systems, methods, and products for automatically updating software products from diverse software vendors on a plurality of end-user, client computer systems. 
     2. Background of the Invention 
     The typical personal computer contains various categories of software products, such as operating system files, utilities, applications, and device drivers, code libraries, and other forms of computer readable or executable information. In some of these categories, such as applications, the personal computer may contain numerous programs in various subcategories. For example, a user may have one or two word processing applications, several graphics applications, and numerous games. Most of these products will come from different software vendors. As used herein “software vendors” includes any entity that distributes software products, even if the entity also manufactures or distributes hardware or other non-software products. These software vendors frequently improve their products, by adding new features, or by fixing known problems, and make these software updates available to their users. These updates may or may not be free. 
     There are at least three significant problems that the vendors and users face in attempting to provide these updates to the user. First, vendors face difficulty and costs in attempting to inform users of their products that the updates are available, and users experience similar difficulties in attempting to ascertain what updates are available. Vendors typically send out mailings to registered users, place advertisements in relevant trade journals and magazines, and engage in other promotional activities. 
     For all of these efforts, many users may remain unaware of the many software updates applicable to their systems until they encounter problems and contact the vendors&#39; technical support organizations. Other users only learn about updates by searching the Internet or on-line services for solutions to their technical problems. Just the shear magnitude of the problem of updating all software products can be overwhelming. Given that a user will have many software products from numerous vendors on her computer, it would be nearly impossible for the user to frequently monitor all of the available distribution channels, journals, Internet forums, and the like, to determine for which of the many software products there are updates available. 
     For example, some vendors maintain sites on the World Wide Web, or electronic bulletin boards (BBS&#39;s) that include information about current updates and products, and enable a user to download such updates. However, such sites are obviously dedicated to a single software vendor, and provide information only about that software vendor&#39;s products, and certainly not about the products of numerous other vendors that may be interest to a given user. Thus, the user would have to search the Internet, and possibly online services, to determine which vendors have such sites. The user would likely to have visit each of these sites individually and determine what software updates are available from each of them. Similarly, even though some on-line services include forums or other mechanisms where users can learn about available updates, this still places the burden on the user to actively seek out this information. Directories or search engines on the Internet, such as Excite, Yahoo, Lycos, or Infoseek merely provide links to software vendor sites, but do not generally attempt to systematically determine which software updates are available, and provide this information to the user, let alone actually update the software on the user&#39;s machine. 
     Another problem is that even once an update has been identified, there is the need to install it in the user&#39;s computer. Many users purchase the software updates by mail order, or the like, and receive them on floppy diskettes. Other users may download the software updates via Internet from the computers of the software vendors, or from on-line services. In any of these cases installing a single update can be a tedious, time-consuming and error-prone process for many users due to the various formats and installation procedures required. Installing updates for all of the numerous software products on a user&#39;s system on a regular basis would be even more difficult and time consuming for the typical user. 
     Finally, many users have concerns about their privacy, and are often resistant to revealing complete information about their software configurations to one or more vendors. However, even for a single vendor, information about which of the vendor&#39;s products are installed on a user&#39;s computer system, and system configuration information is necessary for determining which updates are applicable to the user&#39;s computer system. For example, a certain software update to an accounting program from vendor A might be applicable if the user has a printer from vendor B, and a different software update is applicable if the printer comes from vendor C. The user might not want to let each vendor know about all the components on their system, but this configuration information is necessary to ensure the correct software updated is installed. Still, users are resistant to the prospect of a single vendor storing information profiling the software components that reside on their computer systems. 
     In summary, from the perspective of an individual vendor, the problems are identifying and notifying every user of the vendor&#39;s software of the availability of updates to the software on a timely and useful basis, and ensuring that the proper software updates are installed. From the perspective of the individual user, the problems are systematically and easily identifying which updates are currently available for every piece of software on her system, and resolving the technical difficulties in obtaining and installing such updates. 
     Accordingly, it is desirable to provide a system that automatically determines which software updates from numerous diverse software vendors are currently available, and which are applicable to a given user&#39;s computer system, and installs such user selected ones of such updates on the user&#39;s computer. Further, it is desirable to provide such a system without abridging the privacy of users by obtaining and storing system profile information. 
     SUMMARY OF THE INVENTION 
     A system, method and computer program product are provided for uninstalling software on a computer. In use, a plurality of software products identified on a computer is displayed. Further, a first user instruction to uninstall at least a portion of at least one of the software products from the computer is received. Such first user instruction is received via an interface. Still yet, the at least a portion of the at least one software product is uninstalled from the computer, in response to the receipt of the first user instruction. Also, a second user instruction may be received to cancel the uninstallation. Thus, the uninstallation may be cancelled, in response to the receipt of the second user instruction. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an illustration of a system for providing software updates in accordance with the present invention. 
         FIG. 2  is a flowchart of the overall method for providing software updates to a client computer in accordance with the present invention. 
         FIG. 3  is an illustration of a user interface for registering a new user of the updating service. 
         FIG. 4  is an illustration of a user interface for selecting software updates for installation. 
         FIG. 5  is an illustration of a user interface for confirming installation of a software update. 
         FIG. 6  is an illustration of a user interface for undoing an installation of a software update. 
         FIG. 7  is an illustration of software architecture of the service provider computer system. 
         FIG. 8  is one embodiment of a schema for the update database of the service provider computer. 
         FIG. 9  is an illustration of the software architecture of a client computer. 
         FIG. 10  is a flowchart of further details of analyzing the client computer, determining software updates, and displaying update information. 
         FIG. 11  is a flowchart of the operation of the install monitor. 
         FIG. 12  is a flowchart of the operation of the URL monitor. 
         FIG. 13   a - 13   e  are illustrations of a user interface for registering a software update into the update database. 
         FIG. 14  is one embodiment of a schema for the user profile database. 
         FIG. 15  is one embodiment of a schema for the advertising information database. 
         FIG. 16  is a flowchart of the operation of the recovery module. 
         FIG. 17   a - 17   d  are illustrations of a user interface for registration a software product into the update database. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     System Architecture 
     Referring now to  FIG. 1 , there is shown the architecture of one embodiment of a system for updating diverse software products on users computers in accordance with the present invention In system  100 , there are a plurality of client computers  101  communicatively coupled by a network  106  to a service provider computer  102 . A number of software vendor computers  103  are also communicatively coupled over the network  106  to the service provider computer  102 . The network  106  is preferably the Internet, or other similar wide area network. 
     Each client computer  101  is operated by an end user, and typically has a number of software products installed thereon, such as applications, drivers, utilities and the like. In accordance with the present invention, the client computers  101  includes a client application  104  that communicates with the service provider computer  102  to obtain software updates of software products installed on the client computer  101 . The software architecture of a client computer  101  and client application  104  is further described below with respect to  FIG. 7 . 
     Each software vendor computer  103  coupled to the service provider computer  102  stores software update information, software products, information files, and the like. The software update information includes applications, binary files, text files, and the like, for updating software products installed on client computers  101 , and advertising or other information about such products useful to users for evaluating potential software for updating. Other types of information useful to providing product support, technical service, or the like may also be beneficially provided. In addition, the software vendor computers  103  provide mechanisms for controlling distribution and payment of software updates, such as credit card payment front ends, code authentication and verification subsystems, and the like. These various mechanisms are understood in the art. For example, payment mechanisms may be implemented in compliance with various credit card or debit systems, as known in the art Likewise, authentication and verification may be implemented using conventional encryption techniques. 
     In a preferred embodiment, the network  106  is the Internet, and more specifically, the World Wide Web portion thereof. The various computers thereby support the protocols for FTP, and ZIP, and provide for the display and rendering of HIML, VRML, or other text or Interface description languages. Each computer  101 ,  102 ,  103  has an IP address that specifies its location on the network  106 , thereby allowing such computers to communicate with each other in a conventional manner. Files, such as exectitables, binaries, and text files are identified within the various computers by universal resource locators (URLs) as known in the art. 
     Overall System Operation 
     Referring now to  FIG. 2 , there is shown an overall flow diagram of the process of updating a single client computer  101  in accordance with the present invention. The process here is described with respect to a single client computer  101 . Given the client-server nature of the system, those of skill in the art understand that numerous other individual client computers  101  may interact with the service provider computer  102  in parallel. 
     The update process  200  is typically initiated on the client computer  101 . The user may manually initiate the process, or it may occur automatically, for example at preset periods, such as once a month. Alternatively, the process may be initiated by the service provider computer  102  prompting the client computer  101  at various intervals, or in response to particular events. 
     In each case, the user logs in  201  to the service provider computer  102  with the client application  104  in a conventional manner, providing a user ID, a password, and the like. This information may be manually entered by the user via the client application  104 , or more preferably, stored within the client application  104 , and automatically provided once a connection between the client computer  101  and service provider computer  102  is established If the user is not registered, then the service provider computer  102  in conjunction with inputs by the user, registers  202  the new user of the system.  FIG. 3  illustrates a basic user interface  300  for registering the user. The user identifies himself or herself by name  301  and selects a password  303 . The user may also provide a mailing address  305  and a payment mechanism such as a credit card data  311 , including a credit card number and expiration date, to pay for the services and for any for-fee software updates that the user may access in the course of using the service provided by the service provider computer  102 . An email address  307  is entered to allow the service provider to contact the user by email. The user may select check box  309  to indicate that they want to be notified by email when new software updates are available for software products installed on their computer. When the registration process  202  is completed, the service provider computer  102  returns a unique registration number to the user. This number may be stored on the client computer  101  and used during subsequent logins to identify the user to the service provider computer  102 . 
     The registered users are authenticated  203  by the service provider computer  102 , using conventional authentication mechanisms, such one or more passwords, digital signature, certificates, or the like. Authentication ensures that only users who are properly authorized by the service provider can obtain updates for software products. 
     The client application  104  then analyzes  204  the client computer  101  to determine a list of installed software products. The list of installed software products typically includes applications, system utilities, drivers, and other executables or resources. These software products will typically be from numerous diverse software vendors, a number of whom will maintain software vendor computers  103  on the network  106 . 
     For each of the installed software products on the list, the client application  104  determines  205  if there is an applicable, or relevant update for the software product. This determination is made in consultation with the service provider computer  102 , which maintains, as further described below, a database including a list of available software updates for numerous software products of diverse software vendors. 
     The client application  104  displays  206  the list of applicable software updates to the user, for review and selection thereof of updates for purchase and installation.  FIG. 4  illustrates a sample user interface display  400  of applicable software updates. This display  400  includes the name  401  of each software product identified on the client computer  101 , and remarks  403  displayed next to the name indicating whether the software product is already up-to-date, that is, there are no applicable updates, or, if the product is not current, the list of applicable updates (which may be for the software product itself, or for related products). In those cases where there is an applicable update, the remarks  403  briefly indicate the nature of the software update. In the example of  FIG. 4 , the remarks  403  for the software product Quicken 5.0® by Intuit Inc., indicates an update to provide new features. The user may obtain additional information by selecting a name or remark of a particular software product. The selected product name and remark is highlighted, as shown in  FIG. 4 , and the information about the software update is displayed  207  in an information window  405 . This information may be stored in the service provider computer  101 , or obtained directly from the software vendor computers  103  as needed using URLs associated with such information. The user may limit the list to only those software products that need updating, rather than all installed software products, by selecting check box  407 . 
     The user may select one or more software products to update. To update one of the software products, the user selects the software product for update by selecting (e.g. double-clicking) the line including the software product, or by single clicking on the line, and then clicking the retrieve button  409 . The user may select more than one software update by holding the control key on the keyboard down while single-clicking on the name of each desired software update, followed by selecting the retrieve button  409 . When all the desired updates have been selected, the user may click on the continue button  411  to begin the installation process. 
     For each selected software update, the client application  104  performs an installation process  208 . Referring to  FIG. 5 , the client application  104  displays information  505  for a selected software update, and provides the user the opportunity to confirm  501  or cancel  503  the installation, If confirmed, the client application  104  downloads  209  the software update, along with installation information, such as installation programs, files, and the like. This downloading may be directly from the software vendor computer  103 , using the URL data stored in the service provider computer  102  for the location of the software update on the network  106 . 
     In conjunction with the downloading process  209 , a payment transaction  210  may be conducted whereby the user of the client computer  101  pays for the software update if it is not a free update. The service provider computer  102  may intermediate in this transaction, or merely initiate the transaction by connecting the client application  104  to the computer  103  of the software vendor of the update. If payment information, such as credit card numbers, are stored in the client application  104 , ten this information maybe provided by the client application  104  to the software vendor computer  103 . 
     Once the download and applicable payment are complete, the software update is physically installed on the client computer  101 . Each software update is associated with information that describes the particulars for the installation, such as configuration, decompression or other information. The installation is performed in conformance with such information. 
     In the preferred embodiment, the client application  104  executes  211  an install monitor prior to actually installing the software update. The install monitor, as further described below, records the changes made to the client computer  101  as a result of the installation of the software update. This information is archived by the install monitor and allows the user to “undo” or remove any number of installations, and restore the client computer  101  to its state prior to each such installation. Accordingly, the client application  104  performs  212  the installation, executing any necessary decompression, installation, or setup applications necessary to install the software update. During the installation process  212  the install monitor records  213  any changes made to the system configuration, including changes to various configuration files, additions or deletions of files, and additions or deletions of directories. The changes may be recorded in a variety of manners, such as building descriptions of the modifications of the files, or alternatively, storing copies of files prior to their alteration or deletion. Once the installation is complete, the install monitor archives  214  the changes. This process  208  is repeated for each software update to be installed. 
     Once all of the software updates have been installed, the client applications  104  logs out  215  of the service provider computer  102 , and any necessary payment information for the user may be updated, such as payment based on the number of software updates purchased, the online connection time, and the like. Alternatively, no payment may need to be directly made, as the cost of the service may be included in the cost of the software update charged by the software vendor, who then pays the service provider for the service of coordinating and linking end users to the software vendor&#39;s computer system  103 . 
     At some subsequent point, the user may decide to undo a previous installation, for example, due to dissatisfaction with the software product. The user may use a recovery feature of the client application  104  to undo  216  the installation. A sample user interface  600  for the recovery function is illustrated in  FIG. 6 . The user interface  600  includes a field  601  indicating the previous update to be removed as selected by the user, along with an information window  603  describing the software update. The user confirms the removal of the software update by selecting the undo button  605 , or may cancel with cancel button  607 . The recovery function deletes the files installed for the software update, and using the archived information created by the install monitor during the installation of the product, restores the client computer system  101  to its configuration immediately before the installation of the product. This process  216  includes deleting files and directories that were added, restoring files and directories that were deleted, and restoring files that were otherwise changed In one preferred embodiment, the recovery function is able to undo any installation in a given series of installations, accounting for changes to the configuration of the client computer  101  after a particular installation. In another preferred embodiment, the recovery function undoes installations in the reverse order of their installation. If any payments were originally required from the user for the cost of the software update and the associated service of downloading and installing it, the payments may be credited back to the user when the user undoes the installation. 
     Service Provider Computer 
     Referring now to  FIG. 7 , there is shown one embodiment of the service provider computer  102  in accordance wit the present invention. In terms of hardware architecture, the service provider computer  102  is conventional server type computer, preferably supporting a relatively large number of multiple clients simultaneously for requests for data and other processing operations. The service provider computer  102  includes one or more conventional processors in a processor core  723 , and a suitable amount of addressable memory  700 , preferably on the order of 18-64 Mb. The service provider computer  102  may be implemented with an Intel-based computer including one or more Pentium® processors, or other more powerful computer, such as various models of Sun Microsystems&#39; SparcStations using UltraSparc® processors. The service provider computer  102  executes a conventional operating system  721 , such as Windows NT® from Microsoft Corp,, or one of various UNI-based operating systems, such as Sun Microsystems&#39; Solaris 2.5. The service provider computer  102  fierier includes a network communication protocol layer  719  that implements the necessary TCP-IP communication functions for connecting to the network  106  and communicating with other computers. 
     In accordance with the present invention, the service provider computer  102  includes a number of executable components and database structures useful for managing the software update interactions with the client computer  101  and the software vendor computers  103 . These components include a security module  701 , a communications module  703 , a payment module  705 , database modification tools  707 , an update database  709 , a user profile database  711 , a reporting tools module  713 , a URL monitor module  715 , an advertising/information database  717 , and an activity log  718 , The update database  709  is described here; the remaining components are described further below, 
     Update Database 
     The update database  709  maintains information identifying a large number of software products, information about the software updates that are available from the diverse software product vendors for these software products, information for identifying software products installed on a client computer  101 , and for uniquely distinguishing the versions and names of installed software products. 
     In one embodiment; the update database  709  does not itself store the software updates, but rather stores information, such as URLs, that allows the service provider computer  102  or the client computers  101  to directly access the software updates from the software vendor computers  103 . This implementation is chosen for several reasons. The system  100  is designed to provide software updates for large numbers of software products, on the order of hundreds, and perhaps thousands of products. In this situation, extremely large amounts of storage would be required to store the relevant files. Further, by not storing the software updates themselves, but only links to the software vendor computers  103 , the service provider does not have to make sure that the software updates themselves are always current, but need only maintain the link information, which is administratively easier. In another embodiment, the software updates are stored in the updated database  709 . This implementation is useful, for example, to facilitate synchronization of updates of the database  709  itself with the releases of new software updates for software products, thereby ensuring that the entries in the database  709  are consistent with the current releases of new software updates. 
     Finally, the update database  709  may also store information describing an installation process for installing a software update. This information may include particular configuration, file format, or other data useful to performing the installation of the software update the client computer  101 . This information, if present, may be provided to the client computer  101  to use during the installation of the software update. 
     The update database  709  may be implemented in a variety of ways. Referring now to  FIG. 8  there is shown one implementation of the update database  709 , illustrated as a schema for a relational database. In this embodiment, the update database  709  includes 4 tables: a method table  801 , a product locator table  803 , a product table  805 , and an update table  807 .  FIG. 9  illustrates a flowchart of the process of analyzing the client computer  101  using the tables of the update database  709 . 
     The method table  801  maintains information identifying various methods of analyzing a client computer  101  to determine which software products are installed thereon. The method table  801  includes scan methods  811  and parameters  812 . The various scan methods  812  are designed to cover the variety of different facilities of a client computer  101  that may identify the installed products. For example, in a client computer  101  using Microsofts Windows95 or Windows NT operating system, there is provided a Registry which is designed to maintain indicia of installed software products. The Registry includes various methods that can be called to return information about the software products identified therein. Some of these methods are listed in the scan methods  811 . The parameters  812  are arguments to the Registry methods, for example, identifying specific aspects of the Registry to be searched. 
     While compliance with the Windows95 standard requires that a software vendor&#39;s installation procedure should update the Registry, not all software vendors comply. In this case, information identifying the installed software products is also maintained in the conFIG.sys, system.ini, and the autoexec.bat files. Also, a client computer  101  may be using Microsoft Corp.&#39;s MS-DOS or Windows 3.1 operating systems, which do not use the Registry. Accordingly, the scan methods  811  include methods for reviewing these system files and returning indicia of the installed software products. 
     Each of the scan methods  812  return indicia of the installed products in the form of a number of stings, here scan_string. Each scan_string identifies a product name or file name, or some other data. However, a scan_string may not uniquely identify a product. For this reason, the scan_string is resolved by the product locator table  803 . 
     The product locator table  803  associates individual scan_strings  813  with a product name  815 , instructions  816  for determining a version number or release number, and one or more constraints  814 . The constraint is a rule that uniquely identifies the product given contextual information for the product where there are two entries having identical scan_strings. Constraints include specific directories that include the product, additional entries in the system configuration file, the Registry or the like. If the specified information in these various locations matches the constraint values, then the product name associated with the constraint is the correct product name for the scan_string. In one embodiment, the constraint  814  is an executable procedure that retrieves information in these various locations, and determines from this information whether the product name is a match with the scan_string, according to whether the specified details of the constraint are found in the client computer  101 . 
     Since some of the installed software products will be in their most current version, it is not necessary to update all software products installed on the client computer  101 . Rather, from the list of installed software products, further analysis ( 205 ,  FIG. 2 ) determines for which of these software products is there an applicable software update. A software update is applicable to a client computer  101  if version of the software update is more recent tan the version of the installed software product. 
     Since not all of the software products installed on a client computer  101  need to be updated, the determination of the applicable software updates is usefully made with the product table  805 . The product table  805  associates a product name  815  and a particular release  818  with an update ID  819  identifying a software update for that version of the product. The new version number  820  specifies the new version that would be produced by applying the software update specified by the update ID  819  to the software product identified by the product name and release number. The latest field  821  specifies (Y/N) whether applying the software update would bring the product to its most up-to-date version. 
     Finally, the update table  807  stores the information necessary for performing the software update itself. This table is usefully keyed by the update ID  819 . For each update, there is provided a URL list  823  which contains URLs for the various sites that store the actual binary files for the software update, typically the software vendor computer system  103 , and potentially mirror sites. The URL list  823  is comprised of a number of URL entries, each URL entry having a MRL and a timestamp of the last time the URLE was validated, and flag indicating whether the URL is valid. This allows the URL monitor  715  to ensure that current URL information is maintained in the database. 
     The current cost  824  of the software update is also stored to provide the user with cost information for the software update. 
     The format  825  specifies the file format of the software update files, and thereby indicates the type of processing needed to list all the software update files. In one embodiment, there are six formats and accompanying installation procedures: 
     
       
         
               
               
               
             
           
               
                   
                 TABLE 1 
               
               
                   
                   
               
               
                   
                 Format 
                 Installation Procedure 
               
               
                   
                   
               
             
             
               
                   
                 zip 
                 1) Unzip file with unzip.exe 
               
               
                   
                   
                 2) Run install.exe 
               
               
                   
                 zip 
                 1) Unzip file with unzip.exe 
               
               
                   
                   
                 2) Run setup.exe 
               
               
                   
                 self-extracting archive 
                 1) Execute file to extract 
               
               
                   
                   
                 2) Run install.exe 
               
               
                   
                 self-extracting archive 
                 1) Execute file to extract 
               
               
                   
                   
                 2) Run setup.exe 
               
               
                   
                 file.exe 
                 1) Execute file for self 
               
               
                   
                   
                    extraction and installation. 
               
               
                   
                 unknown 
                 1) use script information to 
               
               
                   
                   
                    perform installation. 
               
               
                   
                   
               
             
          
         
       
     
     With respect to unknown or custom formats, the update table  807  stores in the script  826  either a handle to a custom installation program that is provided either by the software vendor for the update, or by the service provider. In addition, the script  826  also stores information about any conditions that are required for the installation, such as turning off anti-virus programs, or other conflicting programs during the installation process. 
     The description  827  field stores data associated with a description of the software update, such as describing the product features. The description is preferably a UTL to a file on the software vendor computer system  103  that contains the description information. Again, the actual text need not be stored here, but merely a link to where that information is available on the network  106 . 
     The update database  709  has been described as a set of tables. Alternatively, the update database  709  may be implemented in an object oriented framework with each table being a class, and the fields of the tables being attributes and methods of the class, The class type is then usefully defined by the primary key of the table. 
     Client Computer 
     Referring now to  FIG. 9 , there is shown an illustration of the hardware and software architecture of a client computer  101 . A client computer  101  is of conventional design, and includes a processor core  918 , an addressable memory  900 , and other conventional features (not illustrated) such a display, a local hard disk, input/output ports, and a network interface, The display is of conventional design, preferably color bitmapped, and provides output for a user interface for various applications, such as illustrated in  FIGS. 3-6 . The input/output ports support input devices, such as a keyboard, mouse, and the like, for inputting commands and data. The network interface and a network communication protocol  916  provide access to remotely situated mass storage devices, along with access to the Internet, with a TCP-IP type connection, or to other network embodiments, such as a WAN, LAN, MAN or the like. 
     In the preferred embodiment the client computer  101  may be implemented on an Intel-based computer operating under Microsoft Windows 3.1 or Windows95 operating system  917 , or equivalent devices. The client computer  101  includes some number of configuration files  915 , such as the Windows95 Registry, the system.ini, config.sys and other files. 
     The client computer  101  fir has installed thereon software products in the form of applications  912 , operating system utilities  913 , and device drivers  914 , and the like. These various software products ate among those that will be updated by the service provider computer  102 . 
     In accordance with the present invention, the client computer  101  executes the client application  104  in memory  900 . The client application  104  is comprised of a number of executable code portions and data files. These include a security module  901 , a communications module  903 , a payment module  905 , a registration module  904 , an advertising and news module  906 , a system analyzer  907 , a recovery module  908 , an install monitor  910 , and data defining the current state  911  of the application. The client application  104  further maintains in a private area of the computer storage archive files  909  that archive the state of the client computer  101  prior to each update installation. The client application  104  may be provided to the client computer  101  on a computer readable media, such as a CD-ROM, diskette, 8 mm tape, or by electronic communication over the network  106 , for installation and execution thereon, 
     Analysis of Installed Software Products and Determination Of Applicable Updates 
     In the preferred embodiment, the analysis  204  is preferably performed by the client application  104  on the client computer  101  his reduces the network bandwidth required, and the potentially unreliability of non-stateless remote procedure call implementations by having the service provider computer  102  perform the analysis. It further increases the number of simultaneous users of the service provider computer  102 . The analyze process is performed by the system analyzer  907  module of the client application  104 . 
     In this embodiment then, the client computer  101  stores a local copy of the method table  801  and the product locator table  803  and uses these local copies to perform the analysis. 
     Referring now to  FIG. 10  there is shown the process of the system analyzer  907  for analyzing  204  the client computer  101  to determine the list of installed software products. 
     The system analyzer  907  first synchronizes  1001  the method table  801  and the product locator table  803  in the client computer  101  with the current versions held by the service provider computer  102 . Preferably each table is replaced in its entirety; this is likely to be faster than comparing individual entries and updating only those that are out of date. The synchronization may be mandatory or conditioned by version on client computer  101  being older than the version on the service provider computer  102 , as indicated by stored timestamp of last time the update table  709  in the service provider computer  102  was updated. 
     Once the tables are synchronized, the system analyzer  907  can operate locally, for improved efficiency. The system analyzer  907  traverses the entire method table  801 , and invokes  1003  each scan method  812  to search the Registry and configuration files  915  of the client computer  101 . Each scan method  811  outputs a scan_string, as described, specifying some software product installed on the client computer  101 . 
     The system analyzer  907  applies ( 1005 ) each of the scan_strings to the product locator table  803 . The product locator table  803  receives the scan_sting and resolves  1007  the scan_string to determine a product name  815  and a release instruction  816  associated with it. In some cases, the scan_string does not uniquely identify a product name  815 , but matches several product names of installed software products. Accordingly, for each matching entry, the system analyzer  907  obtains  1009  a constraint  814  from the product locator table  803 , and resolves  1009  the constraint to determine whether product on the client computer  101  is in fact the product listed in the entry. The constraint  814  of one of the entries will be satisfied and uniquely identify the product name. 
     Once the specific entry with the correct product name is identified, the system analyzer  907  resolves  1011  the release instruction  816  for the entry to obtain the release or version number of the installed software product The release instruction  816  is preferably an executable procedure that obtains the version number from the named software product, and thus not merely the actual data itself. Using an executable procedure here ensures that the obtained release or version number is actual value for the product. 
     The result obtained by the system analyzer  907  from the product locator table  803  is a list  1013  of the installed software products on the client computer  101 , each product identified by name and the installed version. The system analyzer  907  uses this list to query the service provider computer  102  to determine  205  for which of these products there is an applicable update. 
     For each installed product ( 1002 ) the system analyzer  907  queries the service provider computer  102  to resolve  1004  the name  815  and release number  818  of the product and determine if there a current update  821  for the product. This may be done by passing in the entire list as name, value pairs, or individually quarrying the service provider computer  102 . In either cases, the service provider computer  102  determines if there is an applicable update for a software product by comparing the product name  815  and release information  818  to the product table  805 , and obtaining the information in the latest update field  821 . If there is an update available, in that the release information in the table indicates a version later than the version that is installed on the client computer  101 , then the service provider computer  102  returns  1006  a handle the update ID  819  to the system analyzer  907 . If the release of the software product installed on the client computer  101  is the most recent version, then the service provider computer  102  checks the next entry. This process continues until all of the installed software products are checked. 
     Selection of Software Updates 
     Once all of the installed software products have been reviewed against the product table  805 , the system analyzer  907  will have a list  1007  of the applicable software updates, as those products for which it received an update ID  819  from the service provider computer  102 . The system analyzer  907  can then display  206  the list to the user. An exemplary user interface is described above with respect to  FIG. 4 . 
     The system analyzer  907  can further display  207  additional information for a software update, as illustrated in  FIG. 5 , by querying the service provider computer  102  with the update ID  819  of a particular product to resolve  1008  the update ID  819  on the update table  807  and return information, such as cost, description, and the like. 
     Installation of Software Updates and the Install Monitor 
     The user selects one or more of the list software updates. For each selected update, system analyzer  907  returns the update ED  819  to the service provider computer  102 . The service provider computer  102  resolves the update ID  819  against the update table  807  to obtain the record for this update, including the URL list  823  identifying the location of the relevant update files. This record is returned to the client computer  101 . The client computer  101  accesses the identified ULTRL(s) and downloads the software update files, typically from the software vendor computer  103 , though downloads may be from mirror sites, or the like. The client computer  101  further downloads (from the received URLs) any additional installation files, such as installation executables, and scripts. The client computer  101  also verifies that the software update files are not corrupted, In a preferred embodiment, the client computer  101  employs its security module  901  to verify the integrity of the files to make sure that they have not been corrupted. 
     The software update is then installed  212  by the client application  104  as described, using the format information  825  to determine the particular installation process, and the script  826  to control any custom installation or configuration information. 
     Installation  212  is monitored by the install monitor  910 , which is executed prior to the actual installation. The install monitor  910  documents the state of the client computer  101  prior to installation and the changes made during the installation of a software update, The install monitor  910  operates in the background, and intercepts calls to the file system or other operating system calls that might result in changes to any files in the client computer  101 . Depending on the specific call, the install monitor  910  takes action to preserve the state of the file before the change is made. 
       FIG. 11  illustrates a flowchart of the operation of the install monitor  910 . The install monitor  910  receives operating system calls and messages from the client application  104 . On trapping  1101  an operating system call, the install monitor  910  determines  1103  the type of call. There are three types of calls of interest: calls  1105  that delete a file or directory, calls  1107  that change an existing file by writing to it, and calls  1109  to add new a file or directory. When a file or directory is to deleted, the install monitor  910  first makes  1113  a copy of the existing file or directory to a private area of the client computer&#39;s  101  hard disk or other storage device. The install monitor  910  then lets the operating system  917  delete the file or directory, and waits for the next call. When a file is to be changed  1107 , the install monitor  910  determines  1115  whether this is the first write to the file. If so, then again, the install monitor  910  copies  1119  the file to the private area. If the file has been already changed during the installation, there is no need to copy it again These copy operations  1113 ,  1119  preserve the configuration of the client computer  101  prior to the installation, Finally, if a new file or directory is to be added  1109 , the install monitor  910  stores  1117  the pathname of the new file or directory. This allows the new file or directory to be later deleted during an undo of the installation. For all other types  1111  of operating system calls, the install monitor  910  passes them through without action. 
     The install monitor  910  waits for installation process  212  to complete, preferably indicated by a message from the client application  104 . At this point the complete prior configuration of the client computer  101  is known from the copied files and pathname information. These files and information are compressed  1121  into an archive file  909  and saved on the client computer  101 , along with information identifying the software product installation to which it belongs. This identifying information allows the recovery module  908  to retrieve the archived information and restore the configuration of the client computer  101 . 
     Other Service Provider Software Architecture 
     Referring again to  FIG. 7 , the remaining modules of the service provider computer  102  are now explained. 
     Communication 
     The communications module  703  provides for the establishment, maintenance and termination of network connections between the service provider computer  102  and either the software vendor computers  103  or the client computers  101 . The communications module  703  supports the FTP and  14 m protocols for sending and receiving data over the Internet and the World Wide Web. The communications module  703  generally maintains and establishes separate streams for each connection it maintains. Preferably, the service provider computer  102  supports a large number of connections, possibly several hundred or thousands, at a time. In the event the customer base is so large that an even larger number of simultaneous connections may be required, multiple servers with mirror images of the update database  709  may be used. The communications module  703  also handles login and logout in a conventional manner, though these functions may be incorporated into the security module  701 , below. 
     Security 
     The security module  701  handles the authentication of the user as an authorized user of the service provider computer  102 . The security module  701  may be implemented with conventional authentication mechanisms based on digital signatures, such as public key systems supporting digital signatures, certificates and the like. Suitable security mechanisms include VeriSign Inc.&#39;s Digital ID Center, which incorporates the login and logout functions from the communications module  703 . 
     Additionally, the security module  701  provides for verification of the integrity of software updates that are downloaded from software vendor computers  103  to ensure that such updates have not been altered or infected by computer viruses or other unauthorized modifications. This module may be used, for example, to compute a checksum of the updates and the checksum may be stored in the update database  709 . The checksum may be a simple one, or a cryptographically secure one such as any of the Message Digest (Mn) algorithms proposed by Professor Ronald Rivest and commonly available in programming API&#39;s such as Microsoft&#39;s Cryptographic API standard. Whenever an update is later downloaded to a client computer  101  from a software vendor computer  103 , the checksum of the update may be computed and compared against the one stored in the update database  709 . If the two match, it may reasonably be inferred that the software update was downloaded to the client computer  101  correctly. The security module  701  may also be used to scan for viruses in the software updates stored on the various software vendor computers  103 . 
     Payment 
     The payment module  705  handles payment by the end user to the service provider for the service of providing software updates. The service provider computer  102  maintains a database of its users. This database may be the user profile database  711  or other databases. Each user is charged a service fee for using the service provider computer  102  to download software updates, The fee may be based on a variety of different schedules, such as connection time, number of software updates purchased, annual or monthly subscription fee, or a combination of any of these or other pricing formulas. However charged, the payment module  705  tracks the user&#39;s usage of the service, for example, total the connection time, and maintains a count of the number of software updates downloaded, until the user logs out of the service provider computer  102 . Payment is then charged to the user&#39;s credit card, which was previously supplied by the user during registration. Suitable implementations of the payment module  705  may be created in conformance with the Secure Electronic Transaction specification of Mastercard and Visa. 
     A user&#39;s subscription to the service may be enforced by the payment module  705  in various ways. One example of an algorithm to enforce term subscription is as follows: 
     The user logs in from the client computer  101  to the service provider computer  102 . The payment module  705  determines if the user&#39;s account is current, and if so, accepts the connection to the client computer  101 . If the user&#39;s account is about to expire, for example, within 30 days, or has expired, the payment module  705  prompts the user to renew the subscription. If the user agrees, the subscription fee is charged to the user&#39;s credit card account, and the connection to the client computer  101  is established, allowing the user to use the service as described. If the user refuses to renew, the connection is refused. 
     Fees may also be charged on a per-transaction basis. In this scenario, the fees may be attached to selected transactions. Once example of an algorithm to enforce per-transaction fees is as follows: 
     The client application  104  requests, for a software product to be updated, a transaction permission from the service provider computer  102 . The payment module  705  determines from the update database  705  a specific fee for the transaction, and returns this information, along with a permission, to the client application  104 . The client application  104  displays the fee to the user, who either confirms the transaction or cancels the software update. If the transaction is confirmed, the client application  104  performs the installation process. The payment module  705  is notified if the transaction and installation is successful, and then adds the transaction fee to a running total of fees for the current session. When the users session is complete, the running total of transaction fees is charged to the user&#39;s credit card, and the charges provided to the client application  104  which displays them to the user. 
     In cases where an update is going to be undone by the recovery module  908 , the transaction fees should to be credited back to the user&#39;s credit card account. Here, the client application  104  informs the service provider computer  102  that a software update is to be undone, providing the update ID  819  of the software update The payment module  705  uses the update ID  819  to determine the transaction fee (cost  824 ) to be credited. This amount is passed back to the client application  104  and displayed to the user. The software update is removed by the recovery module  908 , and the payment module  705  is notified of the successful removal. The payment module  705  then subtracts the transaction fee from any current running total of fees. At the close of the session, the payment module  705  either charges or credits the user&#39;s credit card account, as appropriate. 
     Database Modification 
     The database modification tools  707  provide for the maintenance and updating of the update database  709  to include new software updates from various software vendors. The tools  707  provide for the addition of new entries, and the deletion or alternation of existing entries in any of the tables of the update database  709 . 
     Of the various tables, the update table  807 , which contains the information about the current updates for the software products, and the product table  805 , which identifies the various software products for which their are updates, are the most frequently modified. 
     As new software updates become available, either the service provider or the software vendors access the database modification tools  707  to update the database. This is preferably done by completing forms that capture the information used in the tables of the database.  FIG. 13  illustrates a sample form for specifying new update information, or changing existing update information. The form  1300  includes fields for providing the remark  1301  used in describing the update, a URL  1303  for the information on the software update, version information  1305 , software products  1307  affected by the update, the type of update  1309 , known incompatibilities  1311 , filters for locating prior versions of the software product to be updated based on version information  1313 , date information  1315 , and Registry information  1317  (for identifying the software product in the Registry files of the  915  of the client computer  101 ). In addition, the file format  1321  of the update is specified along with a URL  1319  for the network location of software update itself. Finally, the installation procedures  1323  are specified for use in an installation script  826 . This information readily processed in a conventional manner and updated to the appropriate tables of the update database  709 . 
     In order to be supported by the update service of the service provider, software products and the updates to the software products have to be registered in the update database  709 . 
     Registering a software product has the goal of specify sufficient information to identify a product and its version if the product has been installed on a given client computer  101 .  FIG. 17  illustrates a form for registering a software product into the update database  709  for the first time. The registration form  1700  contains fields for the software vendor&#39;s company name  1701 , software product name  1703 , product type  1705 , a method  1707  to identify the software product on the client computer  101 , a unique file name  1707  or character string identifying the product, methods  1709  for verifying version information, file dates  1711 , and directories  1713  on the client computer  101 , The product type  1705  can be a device driver, an application, a plug in (a product which extends the capabilities of another product such as an Internet browser) or an operating system file. 
     The method  1707  to identify the software product preferably specifies a unique file name or a character sting and the location of the file name or string. For example, on the Windows 95 operating system, the name of a sound driver is specified in the Registry location \HKEY_LOCAL_MACHINE\System\CurrentControlSet\control\MediaResources\midi. In this case, the filename of the driver is found in this Registry location. A software product could also be identified by the presence of unique directory names. As noted, in some instances, product names are not unique. 
     The version of the software product that is installed on a client computer  101  may be obtained in one of several ways. It may be the version number, the last modification time-stamp of a file, or it may be specified explicitly in the Registry. The information provided in the registration form is processed after submission and added to the appropriate tables of the update database  709 . 
     Software updates may be identified for inclusion in the update database  709  by the service provider periodically searching the Internet to identify software vendors providing updates of software products. Most software vendors will maintain Internet sites that indicate the presence of new software updates. For each identified software vendor, the service provider downloads the software updates to the updates database  709 . A file format of the software update is determined, and an installation process specified according to the file format of the software update. Finally, the service provider creates an entry in the update database  709  including the URL or network location of the software vendor&#39;s computer system  103  storing the software update, the file format of the software update, and a specification of the installation process. 
     Alternatively, software vendors who contract with the service provider may provide the information about their software products and software updates, e.g. name, file format, and so forth, directly to the service provider, or to the update database  709 . 
     However provided to the update database  709 , registering an update consists of specifying the properties of the software update and the software products and their versions to which the software update is applicable. The properties of the software update preferably include the new version number  820  tat results if the software update is applied to the product, the format  825  of the software update zip file, self-extracting archive, and the like, and the installation steps (script  826 ) required to install the software update on the client computer  101 . The product versions to which the software update is applicable are specified as the products themselves are specified earlier in this section. Also, a URL to a brief description and a full description of the software update, the problems it fixes and features it might add, is preferably included, or the information may be directly stored. 
     As each new update becomes available, a new update entry is created. 
     Either the software vendor or the service provider specifies the product and the software update database entries in conformance with the properties of the software update. 
     User Profile Database 
     The user profile database  711  maintains a profile for each user containing information about which products the user has shown an interest, for example by requesting notification about software updates for specific products, or about new software products. This information is then used to deliver notifications about new updates available for these products to the user, for example by email, or other electronic communications mechanisms. This optional feature of the service provider computer  102  further enhances the value of the service to the user, ensuring timely notification of the availability of software updates and new software products. 
     In this regard, one alternate embodiment of the present invention is the use of email to notify users about new software update information, and new software products for which the user has expressed an interest. Specifically, when a new software update or software product is available, the service provider computer  102  sends an email to those users who have requested notification by email. The email contains information about the software update, and may include the record from the update table  807  about the software update, including the URL data  823  used to access the software update files. The client application  104  would then read the update information, and verify that the software update is indeed applicable to the client computer  101 , and that the client computer  101  satisfies any conditions for installation. If the software updates are approved by the user, the client application  104  downloads the software update, verifies its integrity, and installs the software update directly, without having to login  201  to the service provider computer  102 , and analyze  204  the software products installed on the client computer  101 . In the case of notifications about new software products in which the user had expressed interest, the client application  104  would verify that the user is still interested in the software product and proceed to purchase, download and install it. 
     As a further enhancement of the e-mail notification embodiment, the email sent by the service provider computer  102  includes a specification of conditions a client computer  101  must satisfy for the software update or software product to be installed. This information is essentially the same as that used by the client application  104  to determine the relevant software updates for the client computer  101 . For example, this information includes, for a software update, the older versions of the software product to which it is applicable. This additional information in the email notification is used by the client application  104 , for example, to ensure that the software update is used only once by the user, and can be repeatedly applied 
     The user profile database  711  generally stores information descriptive of each user. This information may include the user ID, password, digital signature, credit card numbers and the like, for use by the security  701 , communications  703 , and payment  705  modules.  FIG. 14  specifies one exemplary schema of the user profile database  711 . In a user table  1400 , each user is identified by user ID  1401 , name  1403 , email address  1405 , the start date  1407  of their subscription to the service, the end or termination date  1409  of the subscription, credit card information  1411  such as number, issuer and expiration date, a user selected password  1413 , and a public key  1415  or other authentication token. As illustrated in  FIG. 3 , the user has the option  309  of requesting notification by email of such software updates. The user table  1400  thus also includes a flag  1416  indicating whether the user so desires to be notified by email. The user table  1400  is keyed by the user ID  1401  to a notification table  1417  that associates the user with selected product names  1419  and their current version  1421 . When a software vendor or the service provider updates the update database  709  with information for a new software update, the notification table  1417  may be scanned to identify those users by user ID  1401  to notify about the update. The email flag  1416  for a user is checked, and if true, the user&#39;s email address  1405  is obtained from the user table  1400  and the user notified by email with information identifying the new software update. 
     Activity Log 
     The service provider computer  102  may be used to log all activities. it performs with respect to the service in the activity log  718 . Of particular interest axe the activities the computer performs in response to user requests for software updates and the like. An illustrative format for the activity log  718  is shown in Table 2. 
     
       
         
               
             
               
               
               
               
               
               
             
           
               
                 TABLE 2 
               
             
             
               
                   
               
               
                 Activity Log 718 
               
             
          
           
               
                 Transaction Id 
                 Activity Type 
                 Date-Time 
                 User Id 
                 Parameters 
                 Response 
               
               
                   
               
               
                 00000001 
                 Login 
                 031296 
                 20198312 
                 password 
                 Success 
               
               
                   
                   
                 093540 
               
               
                 00000002 
                 GetMethods DB 
                 031296 
                 20198312 
                 last version 
                 Methods DB 
               
               
                   
                   
                 093606 
                   
                   
                 or 
               
               
                   
                   
                   
                   
                   
                 Up-to-date 
               
               
                 00000003 
                 GetProducts 
                 031296 
                 20198312 
                 last version 
                 Products- 
               
               
                   
                 Locator DB 
                 093649 
                   
                   
                 Locator DB 
               
               
                   
                   
                   
                   
                   
                 or 
               
               
                   
                   
                   
                   
                   
                 Up-to-date 
               
               
                 00000004 
                 Query Product 
                 031296 
                 20198312 
                 Sound 
                 sb-2.02 
               
               
                   
                 DB 
                 093723 
                   
                 Blaster16, 
               
               
                   
                   
                   
                   
                 2.0 
               
               
                   
                 Query Product 
                 031296 
                 20198312 
                 Myst 1.0 
                 Up-to-date 
               
               
                   
                 DB 
                 093727 
               
               
                 00000005 
                 GetUpdate 
                 031296 
                 20198312 
                 sb16-2.02 
                 Update 
               
               
                   
                 Entry 
                 093751 
                   
                   
                 Entry 
               
               
                 00000006 
                 Download 
                 031296 
                 20198312 
                 sb16-2.02 
                 Success 
               
               
                   
                 Done 
                 093807 
               
               
                 00000007 
                 Installed 
                 031296 
                 20198312 
                 sb16-2.02 
                 Success 
               
               
                   
                 Update 
                 094532 
               
               
                 00000008 
                 Logout 
                 031296 
                 20198312 
                 — 
                 Success 
               
               
                   
                   
                 094730 
               
               
                   
               
             
          
         
       
     
     In this example, the user logged in on Mar. 12, 1996 at 09:35:40 a.m., synchronized their method table  801  and product locator table  803 , queried if software updates for SoundBlaster16 2.0 and Myst 1.0 newer than these product&#39;s last version were available responses indicate that Myst 1.0 was update to date, but the current version of SoundBlaster16 was version 2.02. The user then obtained the update entry for the new versions of SoundBlaster16 describing the software update, downloaded the software updates, installed it, and logged out. 
     Activity types not represented in the example above include Undo of Updates by the recovery module  908 , registering for service, and registering for notification for updates to specific products. 
     In this example, the activities of a single user are represented in the activity log. In an actual system, the activities of several different users would be interspersed in the activity log. 
     Reporting Tools 
     The reporting tools  713  provide support for querying the update database  709 , the user profile database  711  and the activity log  718 . The queries may be about the software products and updates, about the correlation between the types of software updates accessed by various users, and about aggregate data. The databases  709 ,  711  and the activity log  718  together have the potential to provide precise descriptions of the software product profiles of the users. For example, statistical information may be retrieved indicating the number of users of one product, such as SoundBlaster16, who also own a second product, such as Myst This information may be collected and analyzed without necessarily violating the privacy of the individual users. 
     URL Monitor 
     The URL monitor  715  compiles the list of URLs in the update database  709  and verifies on a periodic basis whether they have changed This is done to ensure that the URL information for the software updates is always valid.  FIG. 12  illustrates a flowchart of the URL monitor  715 . The URL monitor  715  traverses  1201  each entry in the update table  807 . This may be done simply in serial order, or by more complex approaches, such as oldest entries first, or some other fashion. For each entry, the UIRL monitor  715  obtains  1203  the URL entries in the URL list  823 , each entry as noted above having a timestamp. The URL monitor  715  links  1205  to the URL in an attempt to connect to the identified site or file via the Internet. 
     The attempted link may fail, and may be repeated some number of times in order to confirm that the URL is actually absent or otherwise incorrect, as opposed to merely a failure of the network service provider or the like. Once it is determined  1207  that the URL is not present, the URL is marked  1209  in the update table  807  as being invalid. 
     If the URL is present, then the timestamp of the URL at the host site is checked, typically by checking the timestamp of the file associated with the URL, or the timestamp of the file that includes the URL, or whichever is later. If the timestamp at the host is newer than the timestamp held in the update table  807 , then it is possible that the underlying file has been changed, and the URL is no longer valid. Again, the URL is marked  1209  as being invalid. If the timestamp of the host is not newer, then the URL monitor  715  continues with the next URL in the URL list  823 . Once all of the URLs in the update table  807  (or the desired number of old ones) have been processed, then the URL monitor  715  notifies  1213  the system administrator of the potentially invalid URLs. The system administrator can then verify the URLs and update them if necessary, resetting the valid flag as the URLs are updated, 
     Advertising &amp; Information Database 
     The access that the service provider computer  102  has to the software profile of the client computers  101  lends itself to sending information, advertisements, and other promotional material that would be appropriate to each specific user, based on the software installed on the user&#39;s computer. Basing information delivery on the installed software products increases the saliency of the information since the user has already manifested an interest in the products. Thus, advertising or promotional information that is derived from or associated with such software products is most likely to be of interest to the user. The service provider computer  102  associates software products with advertising information, and enables this advertising information to be periodically delivered to the user. 
     Furthermore, the nature of downloading and installing software updates is inherently time-consuming; the risks that users perceive in updating usually would mean that they would seldom perform the updates on unattended computers. These factors create an opportunity to the service provider to direct targeted advertisements at the user at appropriate moments when the user runs the client application  104  to update their software, at which time they are present at their computer but not engaged in other activities. The advertisements themselves may be about for-fee software updates (upgrades) that the user may be able to purchase from the service provider or other third parties. Delivery of advertising information during the update process  212  is on the client computer  101  by the advertising/news module  906  The advertising and information database  717  accordingly associates software products with advertising and promotional information. This association may be made in a number of different ways, One mechanism of association is categorizing software products and advertisements,  FIG. 15  illustrates an exemplary schema for the advertising and information database  717  for associating advertising information and software products. 
     The ad table  1500  includes for each advertisement an ad number  1501 , a URL  1503  to the advertisement or information item, and a list  1505  of categories for the advertisement, such as “word processing,” “desktop publishing,” “graphics,” “adventure games,” “communications,” “Internet” and the like. An advertisement or information item may have any number or variety of categories associated with it. The product-category table  1507  lists products names  1511 , product Ms  1509 , and again, a list  1513  of categories for the product. 
     If a user has requested updates to a specific installed product then presumably the user would be interested in advertisements or information for other products that are categorized in the same categories as the installed product. For example, if the user requests an update to an installed copy of Myst 1.0, then this product name is matched against the product name  1511  in the product-category table  1507 , and the categories  1513  for it, such as “interactive game,” are retrieved. The categories  1505  in the category list  1505  of the ad table  1500  are matched against this category, and the URLs  1503  for matching entries retrieved and accessed, with the information being delivered to the user by the client application  104 . The information is preferably presented on the client computer  101  during the installation process  208 - 214 . If there are many matches, then a weighting may be applied to select only those advertisements that match a certain percentage, or number, of categories of the installed products. Other selection criteria may also be applied. The schema of  FIG. 15  is merely illustrative, and implementations other categorization may be used to associate advertising information with software products for delivery to users having such products installed on their computers. 
     Client Application Software Architecture 
     Referring again to  FIG. 9 , the remaining modules of the client application  104  are now explained. 
     Communication 
     The communications module  903  provides complementary functions to the communications module  703  of the service provider computer  102 , including establishing and terminating connection streams, login and logout functions, FT? fractions, and HTTP protocol compliance. All of these functions may be implemented in a conventional manner. 
     Security 
     The security module  901  provides an interface to the security module  701  of the service provider computer  102 , for authentication of the user password, digital signatures, certificates, or the like User passwords or other authentication information are assigned to the user in a conventional manner. The security module  901  may store the authentication information, or the user may be required to manually input the authentication information during login. 
     Payment 
     The payment module  905  provides an interface to the payment module  705  of the service provider computer  102  to effect payment for use of the update service. Payment schedules may vary as described above. Preferably payment is made by credit card authorization. Given one or more payment schedules for use of the service, such as per update, periodic fees, or the like, the payment module may be implemented in a conventional manner. 
     Registration 
     The registration module  904  is used to register new users to the service provider computer  102 . A sample user interface for the registration module  904  is shown in  FIG. 3   
     The registration module  904  obtained the user&#39;s name, address, credit card information, and a user-selected password. The password is entered by the user twice and the two entries matched to ensure that the user did not mistype the password unintentionally. This information is stored in the current state  911  data. The registration module  904  also sends this information to the service provider computer  102 . There the information is verified and a unique registration number assigned to the user and the number is returned to the client application  104 , where the registration module  904  displays the number to the user, and stores the number internally in the current state  911  data. 
     Advertising &amp; News 
     The advertising and news module  906  provides customized information to each user of the service based on their prior interests in various software products and updates, as monitored and stored in the user profile database. The advertising and news module  906  interfaces with the advertising database  717  of the service provider computer  102  to deliver advertising and promotional information the user based on the installed software products on the user&#39;s computer  101 . 
     The advertising and news module  906  provides information in various different modes. In one mode, the advertising and news module  906  obtains ads from the advertising database  717  on a periodic basis, such as once every several hours, according to the installed software products on the client computer  101 , as described above, and caches them locally. If an ad here including other types of information or promotional data) is already present in the cache, it is marked as new, otherwise, the URL of the ad (as determined from the database  717 ) is accessed, and the ad saved in the cached. Ads not marked as new are purged. 
     In a second, complementary mode, the advertising and news module  906  then selects ads from the cache and displays them to the user for a predetermined duration when no other user activity is occurring, such as during the installation process described above, or during an undo operation by the recovery module  908 . 
     Current State 
     The current state  911  is a data store of data describing the present operation of the client application  104 , including for example, user specific information, such as name, address, credit card number, registration or serial number, and which updates have been downloaded and which have been installed. The registration number is used each time the user logs in to the service provider computer  101 . The information about which updates have been downloaded and installed is used to provide the undo capability of the recovery module  908 . 
     Recovery 
     The recovery module  908  provides for undoing, or de-installing previously installed software updates using the archive files  909 . 
     Recovery is an action initiated by the user when he or she is dissatisfied with a software update. when initiated, the effects of a software update previously installed are reversed. The ability of the recovery module  908  to perform the recovery is based on the presence of the archive files  909  created by the install monitor  910  when the software update was first installed, The archive files  909  contain a copy of each file which was deleted or modified during installation along with its original pathname and a list of pathnames of files added during the installation. The archives  909  are preferably kept in a compressed format for space efficiency. Generally, given a specific software update to remove, the recovery module  908  reads the archive file  909  associated with that software update, restores the deleted or modified files to their directories, and deletes the added files or directories. 
       FIG. 16  illustrates one embodiment of the operation of the recovery module  908 . The recovery module  908  receives, as shown in  FIG. 6 , an input of the name of the software update to be removed. This name is associated in the current state information  911  with the particular archive file  909  for that installation. The recovery module  908  closes  1601  all executing applications. Using the name of the software update, or other identifying indicia, the recovery module  908  obtains the archive file  909  associated with the update, and uncompresses  1602  it For each file that is stored in the archive in compressed form, representing a file that the was deleted, the recovery module  908  copies  1603  that file to its original location in the client computer  101 . For each file or directory that is listed as being new, the recovery module  908  deletes  1604  that file or directory. Finally, the recovery module  908  reboots  1605  the client computer  101 . 
     In summary, the present invention enables a useful mechanism for providing updates of various software products from diverse software vendors to a plurality of users, each user having different ones of the software products installed on their computers. The system of the present invention enables the software updates to be continually maintained and verified for correctness, while alleviating both users and software vendors of a substantial burden is communicating with each. The system enables any software vendor to provide software updates to the service provider, ensuring that subscribing users have the software update on a timely basis. Likewise, subscribing users are ensured that they are notified about software updates for all of the software products installed on their computers, without having to individually search out information for each such product. In addition, the present invention enables advertising and other information to be targeted to users based on their interests and preferences and expressed in the software products installed on their computers.