Abstract:
An e-mail processing apparatus, comprising: a communication part that receives e-mails; an accumulator that accumulates the e-mails received via the communication part; a display; and a controller that makes the display display in tree structure, cross relationships between the accumulated e-mails, based on past data of the accumulated e-mails.

Description:
[0001]    This application claims priority under 35 U.S.C. §119 to Japanese Patent Application No. 2006-228491 filed on Aug. 24, 2006, the entire disclosure of which is incorporated herein by reference in its entirety. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to an e-mail processing apparatus, which is applied to a MFP (Multi Function Peripheral), e.g. a multifunctional digital complex machine, and other image forming apparatuses; an e-mail processing method; and a recording medium having a program recorded therein to make a computer execute e-mail processing. 
         [0004]    2. Description of the Related Art 
         [0005]    The following description sets forth the inventor&#39;s knowledge of related art and problems therein and should not be construed as an admission of knowledge in the prior art. 
         [0006]    With the spread of e-mail in recent years, in companies, offices and others, employees become to exchange more frequently e-mails with or without an attachment file using a mailing list, to achieve higher business productivity. 
         [0007]    A heretofore known art that has been conventionally used is that members of mailing list are registered in a MFP and a series of e-mails are recorded in a recording area that is called “BOX”, so that the members of mailing list easily can track things backward. 
         [0008]    According to the art, if a user transfers to a MFP an e-mail that is once distributed using a mailing list, the MFP generates a BOX for the mailing list, then stores in the BOX the received e-mail with a file attached to the e-mail. Subsequently, the MFP inquires a server for members (mail addresses) of the mailing list, then gives a permission to access the BOX to login users having the mail addresses. Further, the MFP inquires for members of the mailing list at predetermined intervals. Then, if there is a member newly added to the mailing list, the MFP adds the member as a login account of the MFP itself, and if the MFP is not a member of the mailing list, the MFP adds the mail address of the MFP itself in the mailing list. 
         [0009]    Meanwhile, another art disclosed in the Japanese Unexamined Laid-open Patent Publication No. 2003-67306 is that a file attached to a transmitted e-mail is picked up, and administration information about the attachment file that is picked up is generated, in order to administer the attachment file. 
         [0010]    With the conventional methods described above, members of a mailing list can read the e-mails and the attachment files of the past. However, because such a large amount of e-mails and attachment files are exchanged and a large amount of files are stored in a BOX, it is needed to devote substantial time to search out a target file from the BOX. 
         [0011]    To address the inconvenience, the last updated files are conventionally searched according to update dates/times, file versions, and others. However, in cases where files are updated by a series of the complex processings like in the way above, not only file versions are not administered correctly, but also attachment files cannot be tracked by update dates/times. Thus, it is the only one method to search out a target file to check contents of the respective files in chronological order. 
         [0012]    In addition, with the art disclosed in the patent document mentioned above, although files are differentiated by the categories, it is still inconvenient that a target file cannot be searched out quickly because there are a lot of files with the same file names, and with the same updated time/date, and others. In addition, although a target can be narrowed down to some related files, there is still a need to take a view of all the related files consequently, and this is such a significant load of laborious work. 
         [0013]    In circumstances where e-mails are used for business, even file names of attachment files and mail subjects are frequently changed in many cases. Thus, in order to achieve higher business productivity, it is inevitable to bother to track e-mails and attachment files that have been exchanged. 
         [0014]    The description herein of advantages and disadvantages of various features, embodiments, methods, and apparatus disclosed in other publications is in no way intended to limit the present invention. Indeed, certain features of the invention may be capable of overcoming certain disadvantages, while still retaining some or all of the features, embodiments, methods, and apparatus disclosed therein. 
       SUMMARY OF THE INVENTION 
       [0015]    The preferred embodiments of the present invention have been developed in view of the above-mentioned and/or other problems in the related art. The Preferred embodiments of the present invention can significantly improve upon existing methods and/or apparatuses. 
         [0016]    An object of the present invention is to provide an e-mail processing apparatus enabling e-mails and attachment files of the past to be checked easily. 
         [0017]    Another object of the present invention is to provide an e-mail processing method enabling e-mails and attachment files of the past to be checked easily. 
         [0018]    Yet another object of the present invention is to provide a recording medium having a program recorded therein to make a computer execute e-mail processing. 
         [0019]    According to a first object of the present invention is an e-mail processing apparatus, comprising:
       a communication part that receives e-mails;   an accumulator that accumulates the e-mails received via the communication part;   a display; and   a controller that makes the display display in tree structure, cross relationships between the accumulated e-mails, based on past data of the accumulated e-mails.       
 
         [0024]    According to a second object of the present invention is an e-mail processing apparatus, comprising:
       a communication part that receives e-mails;   an accumulator that accumulates the e-mails received via the communication part;   a display;   an acquirer that acquires from a server, e-mails that are related to an optional e-mail selected by a user among the e-mails accumulated in the accumulator; and   a controller that makes the display display in tree structure, cross relationships between the acquired e-mails.       
 
         [0030]    According to a third object of the present invention is an e-mail processing method, comprising:
       receiving e-mails;   accumulating the received e-mails; and   making a display display in tree structure, cross relationships between the accumulated e-mails, based on past data of the accumulated e-mails.       
 
         [0034]    According to a fourth object of the present invention is an e-mail processing method, comprising:
       receiving e-mails;   accumulating the received e-mails;   acquiring from a server, e-mails that are related to an optional e-mail selected by a user among the accumulated e-mails; and   making a display display in tree structure, cross relationships between the acquired e-mails.       
 
         [0039]    According to a fifth object of the present invention is a recording medium having a program recorded therein to make a computer execute:
       receiving e-mails;   accumulating the received e-mails; and   making a display display in tree structure, cross relationships between the accumulated e-mails, based on past data of the accumulated e-mails.       
 
         [0043]    According to a sixth object of the present invention is a recording medium having a program recorded therein to make a computer execute:
       receiving e-mails;   accumulating the received e-mails;   acquiring from a server, e-mails that are related to an optional e-mail selected by a user among the accumulated e-mails; and   making a display display in tree structure, cross relationships between the acquired e-mails.       
 
         [0048]    The above and/or other aspects, features and/or advantages of various embodiments will be further appreciated in view of the following description in conjunction with the accompanying figures. Various embodiments can include and/or exclude different aspects, features and/or advantages where applicable. In addition, various embodiments can combine one or more aspect or feature of other embodiments where applicable. The descriptions of aspects, features and/or advantages of particular embodiments should not be construed as limiting other embodiments or the claims. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0049]    The preferred embodiments of the present invention are shown by way of example, and not limitation, in the accompanying figures, in which: 
           [0050]      FIG. 1  is a schematic diagram showing a configuration of an image processing system in which an e-mail processing apparatus according to one embodiment of the present invention is used; 
           [0051]      FIG. 2  is an external perspective view of a MFP as an e-mail processing apparatus; 
           [0052]      FIG. 3  is a block diagram showing an electrical configuration of the MFP; 
           [0053]      FIG. 4  is a diagram showing an example of data description in a header followed by an e-mail body; 
           [0054]      FIG. 5  is a diagram showing e-mails and attachment files exchanged among mail members, in chronological order; 
           [0055]      FIG. 6  is a diagram showing an example of e-mails and attachment files displayed in tree structure; 
           [0056]      FIG. 7  is a diagram showing another example of e-mails and attachment files displayed in tree structure, wherein duplicated attachment files are displayed in a different form; 
           [0057]      FIG. 8  is a diagram showing yet another example of e-mails and attachment files displayed in tree structure, wherein the e-mails carrying attachment files are picked up from  FIG. 7 ; 
           [0058]      FIG. 9  is a diagram showing still yet another example of e-mails and attachment files displayed in tree structure, and duplicated files are removed and e-mails carrying original attachment files and the original attachment files are picked up from  FIG. 8 ; 
           [0059]      FIG. 10  is a diagram showing a display screen where all the e-mails and the attachment files are displayed in tree structure; 
           [0060]      FIG. 11  is a diagram showing a display screen where duplicated attachment files are displayed in a different form; 
           [0061]      FIG. 12  is a diagram showing a display screen where e-mails carrying attachment files and the attachment files are displayed; 
           [0062]      FIG. 13  is a diagram showing a display screen where e-mails carrying original attachment files and the original attachment files are displayed; 
           [0063]      FIG. 14  is a flowchart of a process starting with e-mail reception, to generate information to be displayed in tree structure; 
           [0064]      FIG. 15  is a diagram showing a list of the e-mails stored in a BOX of a user; 
           [0065]      FIG. 16  is a diagram showing a list of all the e-mails having the same message-ID as an e-mail specified by a user; 
           [0066]      FIG. 17  is a diagram showing an example of the e-mails and the attachment files displayed in tree structure, wherein those are picked up from the list of  FIG. 16 ; 
           [0067]      FIG. 18  is a diagram showing another example of e-mails and attachment files displayed in tree structure, wherein the duplicated attachment files are displayed in a different form; 
           [0068]      FIG. 19  is a diagram showing yet another example of e-mails and attachment files displayed in tree structure, wherein the e-mails carrying attachment files and the attachment files are picked up from  FIG. 18 ; 
           [0069]      FIG. 20  is a diagram showing still yet another example of e-mails and attachment files displayed in tree structure, and duplicated files are removed and e-mails carrying original attachment files and the original attachment files are picked up from  FIG. 19 ; 
           [0070]      FIG. 21  is a flowchart of a process to display related e-mails and attachment files in tree structure, by specifying an e-mail or an attachment file in a BOX; and 
           [0071]      FIG. 22  is a flowchart of a process to request for an attachment file, by specifying the attachment file. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0072]    In the following paragraphs, some preferred embodiments of the invention will be described by way of example and not limitation. It should be understood based on this disclosure that various other modifications can be made by those in the art based on these illustrated embodiments. 
         [0073]      FIG. 1  is a schematic diagram showing a configuration of an image processing system in which an e-mail processing apparatus according to one embodiment of the present invention is used. 
         [0074]    As shown in  FIG. 1 , the image processing system comprises MFPs  1  and  2  as one or more e-mail processing apparatuses, one or more personal computers (PCs)  31 , and one or more FAX terminals  32 . And those MFPs  1  and  2 , PC  31  and FAX terminal  32  are interconnected via a communications line  4  for mutual communication. 
         [0075]    A LAN, the Internet, a dedicated line, or a public line is used as the communications line  4 . 
         [0076]    Computer names such as “PC001” and “PC002” are provided as identification information for the MFPs  1  and  2 , and PC  31 , to identify each of them. Instead of such computer names above, IP addresses can be also used as identification information. Numbers of so-called fixed line phone or IP phone are provided for the respective FAX terminals. 
         [0077]    Hereinafter, it will be explained about the MFP  1  on behalf of MFPs  1  and  2 , since the MFP  2  has the same configuration as the MFP  1 . 
         [0078]      FIG. 2  is an external perspective view of the MFP  1 , and  FIG. 3  is a block diagram showing an electrical configuration of the MFP  1 . 
         [0079]    As shown in  FIG. 2  and  FIG. 3 , the MFP  1  is an all-in-one apparatus having functions of copy, network-print, scan, FAX, document server and etc. 
         [0080]    It is possible to set users not to be permitted to use the MFP  1  unless authentication by user information registered in the MFP  1  succeeds. 
         [0081]    The MFP  1  comprises an operation part  10 , a scanner  13 , a printer  14 , a finisher  15 , a communication interface  16 , a document feeder  17 , a sheet feeder  18 , a CPU  20 , a RAM  21 , a ROM  22 , and a data memory  23 . 
         [0082]    The operation part  10  comprises an operation panel  11  and a display  12 . 
         [0083]    The operation panel  11  comprises a plurality of keys for inputting characters such as numbers, letters and marks, a sensor (not shown in the Figure) for sensing pressed keys, a transmission circuit (not shown in the Figure) for transmitting to the CPU  20  signals indicating the pressed keys, and others. 
         [0084]    The display  12  displays screens for letting users read messages or instructions, input instructions for setting and processing, confirm image formed and processing results drawn by the MFP  1 , and etc. A touch panel liquid crystal (LCD) that is used as the display  12  for example, has a function to sense locations on itself, where are touched by users with fingers or others, and then transmit to the CPU  20  signals indicating the sensing results. 
         [0085]    As described in the way above, the operation panel  11  and the display  12  serve as a user interface (I/F) for users to operate the MFP  1  directly. 
         [0086]    The scanner  13  photoelectrically reads information of image such as photos, characters, drawings, etc. carried by a document to obtain image data. The obtained image data is converted to digital data by an image processor not shown in FIG.; given various kinds of well-known image processings; and transmitted to the printer  14  for image printing, to the communication I/F  16  for data transmission, or to the memory  23  for data recording for future use. 
         [0087]    The printer  14  prints on recording sheets made of paper, film, or etc., the image data read by the scanner  13 , or the image data received by the communication part  16  from external devices, or the image data accumulated in the memory  23 . 
         [0088]    The sheet feeder  18 , which is located in the lower region of the body of the MFP  1  for example, provides the printer  14  with recording sheets suitable for the image to be printed. 
         [0089]    Upon receiving printed sheets that are the recording sheets whereon the image is printed, the finisher  15  executes processings such as stapling and punching on the printed sheets according to mode settings, and discharges them into a tray  24 . 
         [0090]    The communication I/F  16  comprises a sender  16   a,  a receiver  16   b,  and others, and exchanges data with the PC  31  and the FAX terminal  32 . A NIC (Network Interface Card), a modem, or a TA (Terminal Adaptor) is used as the communication I/F  16 . 
         [0091]    The data memory  23  comprises a hard disk (hereinafter, referred to as “HDD”)  23 H having a plurality of boxes (BOXes) that are memory areas, a card reader/writer  23 R, and others. 
         [0092]    The card reader/writer  23 R readouts data from a memory card  91  that is a CompactFlash, a SmartMedia or etc., and writes data in the memory card  91 . 
         [0093]    The memory card  91  is used chiefly for data communication with the PC  31  without involving the communication line  4 , and is also used for data backup. 
         [0094]    The HDD  23 H has storage areas for storing image data read out by the scanner  13 , image data received by the communication I/F  16  from external devices, and records of job modes. 
         [0095]    Data recorded in the HDD  23 H can be accessed from the MFP  2  via the communication line  4 . 
         [0096]    The CPU  20  controls the overall operations in the MFP  1  by executing a program recorded in the ROM  22  or another program loaded in the RAM  21 . 
         [0097]    Meanwhile, the PC  31  has an installed application program and a driver for giving instruction against the MFP  1 . Thus, users can remotely operate the MFP  1  using the PC  31 . 
         [0098]    Hereinafter, the method for displaying in tree structure cross relationships of e-mails and attachment files stored in the MFP  1 , will be explained. 
       Embodiment-1 
       [0099]    In this embodiment, based on the assumption that there is a group consisting of some mail members of a mailing list and e-mails exchanged within the group are recorded in its own received file BOX, the MFP  1  having the shared mailing BOXes in the HDD  23 H displays e-mails in tree structure. Thus, e-mails are displayed in tree structure by groups, and the past e-mails exchanged within the group can be checked extremely easily. 
         [0100]      FIG. 4  shows an example of data description in a header followed by an e-mail body. 
         [0101]    In  FIG. 4 , data description in a header begins with the items as following: 
         [0102]    Received: forwarding routes of the e-mail 
         [0103]    Message-ID: a unique ID number of the message (e-mail) 
         [0104]    From: a mail address of the originator of the message (e-mail) 
         [0105]    To: a destination mail address of the e-mail 
         [0106]    References: a series of message IDs related to the e-mail 
         [0107]    Subject: a subject of the e-mail 
         [0108]    Date: transmitting date and time of the e-mail 
         [0109]    In the MFP  1 , received e-mails are administered by their own message IDs that are provided in the headers of the respective received e-mails. Message IDs are unique for the respective e-mails, different from one e-mail to another, and are never duplicated. 
         [0110]    There listed in the “references” in the messages (e-mails) received by a recipient, message IDs of the past e-mails related to the received e-mail. 
         [0111]    A message ID, references, a mail subject, and properties of the attachment file are acquired from the header of the received e-mail, and the description in the mail header and linkage destination information of the e-mail data are stored in an e-mail ID administration file. 
         [0112]    More specifically, all the message IDs described in the “references” are scanned, then it is checked whether or not there are the same message IDs in those already stored in the BOX of the MFP  1 . If there are the same message-IDs in those already stored in the BOX, an e-mail that corresponds to the latest message-ID in the “references” (the message-ID listed at the end) is related to the received e-mail. 
         [0113]    In this way as described above, e-mails that have been exchanged are stored and administered to display in tree structure. Thus, cross relationships between past e-mails can be checked by matching message IDs, and the past e-mails are converted to data to be displayed in tree structure according to the cross relationships, and then the data is recorded in the e-mail ID administration file. 
         [0114]    As for each of the attachment files, it is checked by its properties, whether or not there is the same attachment file in those already stored. If there is the same attachment file in those already stored, the first received file is defined as an original one, and the later received files are removed. Then the linkage destination is updated with the original file, and a deleting record is added in the e-mail ID administration file. 
         [0115]    Hereinafter, file display methods using the e-mail ID administration file will be explained. 
         [0116]      FIG. 5  shows a list of e-mails exchanged among mail members of a mailing list. With the conventional display method, files are listed simply in chronological order as shown in  FIG. 5 , and it is significantly difficult to find a target file from the list. 
         [0117]      FIG. 6  shows an example of files displayed on the display  12  based on the e-mail ID administration file. Contrary to the chronological display method shown in  FIG. 5 , in this embodiment, all the e-mails are administered by their own message IDs in the e-mail ID administration file to be displayed in tree structure. In  FIG. 6 , all the files organized in the trees are displayed with cross relationships between the files on the display  12  in the operation panel  10 . In addition, mail subjects and attachment files are also displayed in the trees according to the cross relationships of the message IDs. 
         [0118]    In this embodiment, one tree corresponds to one topic about which e-mails are exchanged. All the past files related to a large amount of the accumulated e-mails can be checked in the trees, and a target file can be searched out easily checking them. 
         [0119]    If the screen of the display  12  in the MFP  1  is rather small, the latest file may be displayed in a pop up window, an expanded window, or etc. 
         [0120]    Although not shown in  FIG. 6 , the screen can be switched to other screens where the files organized by senders, receivers and transmitting dates/times are displayed similarly in tree structure. 
         [0121]    In addition, if there is an e-mail with a “cc” destination, the destination also may be displayed additionally. Thus, destination address of an e-mail can be checked. 
         [0122]    In this embodiment as mentioned above, if there is the same attachment file (are the same attachment files) in those already received, the first received file is defined as an original one, and the later received files are removed. Then the attachment file linkage destination is updated with the original file. 
         [0123]    In  FIG. 7 , the removed attachment files are displayed in a different form to indicate those are transmitted without updates. The portions marked with hatching indicate the removed files (referred to as “link files” in FIG.), and those may be also marked with a different color. Thus, the e-mails and attachment files of the past, which are exchanged regarding a tree (a topic about which e-mails are exchanged), can be checked easily. Although not shown in FIG., the files organized by duplicated files may be displayed similarly in a different form. 
         [0124]      FIG. 8  shows an example where e-mails not carrying any attachment file are removed from the tree in  FIG. 7 . In this embodiment, data amount is reduced for easy identification. 
         [0125]      FIG. 9  shows an example where e-mails carrying duplicated attachment files and the duplicated attachment files are removed from the tree in  FIG. 8  and e-mails carrying original attachment files and the original attachment files are displayed. In this embodiment, un-updated attachment files such as those transmitted by mistake are not displayed, and a target attachment file can be searched out more easily. 
         [0126]    Further, as shown in the tree, there are four topics with “001” and “002” serieses of files; “003” and “004” serieses of files; “005”, “006” and “007” serieses of files; and “008” and “009” serieses of files. As for the “003” and “004” serieses of files, for example, a “file 003 updated” a first “file 004” and a second “file 004” (other than the former “file 004” although the file names are the same) are originated from the “the latest file 003”, and the second “file 004” followed by the “file 003 updated” and the first “file 004” is the latest file for the topic. Thus, a target file can be searched out easily by checking the files. 
         [0127]    As described above, a target file can be searched out easily from serieses of files by checking cross relationships between the files. 
         [0128]    Hereinafter, switching tree-displayed screens that are displayed on the display  12  will be explained with reference to  FIG. 10 ,  FIG. 11 ,  FIG. 12  and  FIG. 13 . 
         [0129]      FIG. 10  is a tree-displayed screen D 1  (corresponding to  FIG. 6 ) where all the e-mails and the attachment files are displayed in tree structure, and  FIG. 11  is a display screen D 2  (corresponding to  FIG. 7 ) where duplicated attachment files that are removed are displayed in a different form.  FIG. 12  is a display screen D 3  (corresponding to  FIG. 8 ) where attachment files are displayed, and  FIG. 13  is a display screen D 4  (corresponding to  FIG. 9 ) where original attachment files are displayed. 
         [0130]    On the lower side of the respective display screens D 1 , D 2 , D 3  and D 4 , there is a central button  101  for indicating a title of the current screen, a selection button  102  for switching to another display screen where the information is more simplified than the current screen and a selection button  103  for switching to another display screen where the information is further segmentalized than the current screen. 
         [0131]    For example, if the “display duplicated files” button  102  in the right of the screen is touched in the display screen D 1  in  FIG. 10  for displaying all the information in tree structure, the screen is switched to the screen D 2  in  FIG. 11 . Then, if the “display attachment files” button  102  in the right of  FIG. 11  is touched, the screen is switched to the screen D 3  in  FIG. 12 . And then, if the “display whole trees” button  103  in the right of  FIG. 11  is touched, the screen is returned to the screen D 1  in  FIG. 10 . 
         [0132]    If the “display original files” button  102  in the right of the screen is touched in the screen D 3  in  FIG. 12 , the screen is switched to the screen D 4  in  FIG. 13 . Then, if the “display duplicated files” button  103  in the left of  FIG. 13  is touched, the screen returns to the screen D 2  in  FIG. 11 . And then, if the “display attachment files” button  103  in the left of the screen  14  in  FIG. 13  is touched, the screen is returned to the screen D 3  in  FIG. 12 . 
         [0133]    A process starting with e-mail reception, to generate information to be displayed in tree structure will be explained with reference to the flowchart in  FIG. 14 . This process and the processes in the flowcharts shown in the following Figures are executed by the CPU  20 , according to a program recorded in the ROM  22 . 
         [0134]    As shown in  FIG. 14 , when an e-mail is received, properties of the attachment file are acquired in Step S 1 , and the message ID is acquired in Step S 2 . Then, it is judged in Step S 3 , whether or not there is any message ID in the “references” field of the e-mail. 
         [0135]    If there is not any message ID in the “references” field (NO in Step S 3 ), the routine proceeds to the Step S 11  where the acquired message ID is registered in the e-mail ID administration file to be displayed in a new tree, and then the routine proceeds to the Step S 10 . 
         [0136]    If there is a message ID (are message IDs) in the “references” field (YES in Step S 3 ), it is judged in Step S 4 , whether or not there are the same message IDs already registered in the e-mail ID administration file. If there are not the same message IDs already registered (NO in Step S 4 ), the routine proceeds to Step S 11 . If there are the same message IDs already registered (YES in Step S 4 ), then in Step S 5 , the message IDs are matched to judge which one is the latest, and the routine proceeds to Step S 6 . 
         [0137]    In Step S 6 , the routine waits until it is judged which message ID is the latest (NO in Step S 6 ), and if it is judged (YES in Step S 6 ), then in Step S 7 , the latest message-ID is related to the message ID. 
         [0138]    Subsequently in Step S 8 , the message-IDs older than the related message-ID in the “references” field are removed. 
         [0139]    In Step S 9 , the message-ID and the message-IDs in the “references” field that are acquired are registered in the e-mail ID administration file, then a process for registration completion is executed in Step S 10 , and then the routine terminates. 
       Embodiment-2 
       [0140]    In the present embodiment, based on the assumption that an e-mail or an attachment file stored in an individual BOX in the MFP  1  is specified by a user, the related e-mails are acquired from the mail server  31  and displayed in tree structure with cross relationships between the e-mails. 
         [0141]    When an e-mail or an attachment file stored in an individual BOX in the MFP  1  is specified by a user, the MFP  1  acquires from the server  31  not only the e-mails sent to the user but also the e-mails sent from the user, by checking those header information, then acquires also the header information of the e-mails and information of the attachment files (file properties). 
         [0142]    All the described message IDs from the “references” field of the acquired header information are scanned, and it is checked whether or not there is among the scanned message-IDs the same message-ID as those described in the “references” of the specified e-mail or an e-mail having the specified attachment file. 
         [0143]    If there is, similarly to the Embodiment-1, the respective acquired e-mails are related to each other based on the latest message ID (the message ID listed at the end), and a tree information file is generated to display the past e-mails in tree structure. 
         [0144]      FIG. 15  shows a list of e-mails stored in a BOX of a user A. 
         [0145]    As shown in  FIG. 15 , when an e-mail or an attachment file (file  003 ) is specified (the item with a mark “★” in FIG.), the MFP  1  acquires not only the e-mails sent to and from the user from the mail server  31 , but also header information and attachment file information of all the acquired e-mails having in the “references the same message ID as the specified e-mails or an e-mail carrying the specified attachment file”. 
         [0146]      FIG. 16  shows a list of all the e-mails having in the “references” the same message-ID as the specified e-mail among the e-mails sent to and from the user A. 
         [0147]      FIG. 17  shows an example of the e-mails from the list, which are displayed in tree structure based on the tree information file. 
         [0148]    As shown in  FIG. 17 , more than three times the amount of attachment files than those in the BOX (shown in  FIG. 15 ) are displayed in the trees. Thus, related files including files that could not been searched in the conventional display method can be displayed. 
         [0149]    In  FIG. 17 , a mark “◯” indicates that it is a file stored in a BOX of a user, and the mark “★” indicates that it is a file specified by the user. 
         [0150]      FIG. 18  shows an example of e-mails picked up from the tree in  FIG. 17 . The e-mails are those carrying duplicated attachment files, and the duplicated attachment files are displayed in a different form, and the duplicated attachment files are marked with hatching in this embodiment. With the display method, users understand which are duplicated files and can search out a target attachment file easily. 
         [0151]      FIG. 19  shows an example of e-mails picked up from the tree in  FIG. 18 . The e-mails are other than those not carrying attachment files and displayed in tree structure. With the display method, data amount is reduced for easy identification. 
         [0152]    In  FIG. 20 , duplicated files are removed from  FIG. 19 , and the e-mails are those carrying original attachment files. Since it is a duplicated attachment file that the user specified in this embodiment, the specified file is displayed with the mark “★” in  FIG. 19 , meanwhile the original file is displayed with a star mark of density that is different from the mark “★” (the file is displayed with the mark “⋆” in  FIG. 20 ). 
         [0153]    With the display method, wasted files such as files transmitted without updates by mistake are not displayed, and a target file can be searched out more easily. 
         [0154]    Further, as understood from the tree, there are four topics regarding the file “file 003” that is specified by the user, and “001” and “002” serieses of files, “003” and “004” serieses of files, “005”, “006” and “007” serieses of files, and “008” and “009” serieses of files are provided for the topics, respectively. 
         [0155]    In addition, as understood from the tree, a “file 003 updated”, a first “file 004” and a second “file 004” (other than the former “file 004” although the file names are the same) are originated from the “the latest file 003”, and the second “file 004” followed by the “file 003 updated” and the first “file 004” is the latest file for the topic. Thus, a target file can be searched out easily by checking the files. 
         [0156]    Hereinafter, a process for displaying e-mails and attachment files in tree structure when an e-mail or an attachment file in a BOX of the MFP  1  is specified by a user will be explained with reference to the flowchart in  FIG. 21 . 
         [0157]    In  FIG. 21 , when an e-mail or an attachment file in a BOX of the MFP  1  is specified by a user, e-mails sent to and from the recipient of the specified e-mail are acquired from the mail server  31  and message IDs and attachment file information of the e-mails are acquired in Step S 21 . Then in Step  22 , the tree information file is generated based on the message IDs and the attachment file information. 
         [0158]    In Step  23 , headers of the e-mails in the BOX are scanned, then properties of the attachment files are acquired from the mail headers in Step S 24 , and then the message-IDs are acquired in Step S 25 . 
         [0159]    In Step  26 , it is judged whether or not there are the same message IDs in the tree information file, and if there are not the same message IDs in the tree information file (NO in Step S 26 ), the routine proceeds to Step S 28 . If there are the same message IDs in the tree information file (YES in Step S 26 ), the information that the e-mails having the same message-IDs are already stored in the BOX is added in the tree information file in Step S 27 . Then the routine proceeds to Step S 28 . 
         [0160]    In Step  28 , it is judged whether or not the process of scanning headers of the e-mails in the BOX is completed, if the process of scanning headers of the e-mails in the BOX is not completed (NO in Step S 28 ), the routine goes back to Step S 23 . If the process of scanning headers of the e-mails in the BOX is completed (YES in Step S 28 ), the information that the e-mails having the same message-IDs are already stored in the BOX is additionally displayed in Step S 29 , and the information that the specified e-mail is stored in the BOX is additionally displayed in Step S 30 . Then in Step  31 , a tree display completion process is executed, and the routine terminates. 
         [0161]    If a user would like to have an attachment file that is not stored in the BOX, he/she may send to an originator of the attachment file, an e-mail requesting to re-send the e-mail having the attachment file, by clicking the attachment file on the screen. 
         [0162]      FIG. 22  shows a flowchart of a process to acquire an attachment file, by specifying the attachment file among those displayed in tree structure. 
         [0163]    In  FIG. 22 , in Step S 41 , it is judged whether or not the attachment file is in the BOX. If the attachment file is in the BOX (YES in Step S 24 ), then an application is activated to open the specified attachment file in Step S 42 , and the routine terminates. 
         [0164]    If the attachment file is not in the BOX (NO in Step S 24 ), it is judged in Step S 43 , whether or not the attachment file is in the mail server  31 . If the attachment file is in the mail server  31  (YES in Step S 43 ), the attachment file is acquired from the mail server  31  in Step S 44 , then the routine proceeds to Step S 42 . 
         [0165]    If the attachment file is not in the mail server  31  (NO in Step S 43 ), the mail address originating the attachment file is acquired by the message ID of the e-mail carrying the attachment file in Step S 45 , then in Step S 46 , an e-mail requesting to re-send the attachment file is sent to the acquired mail address originating the attachment file. 
         [0166]    As explained above, in this embodiment, cross relationships between e-mails and attachment files of the past are displayed in tree structure. Thus, the e-mails and the attachment files of the past in the trees can be checked easily, and an attachment file can be tracked by checking those. In this way, a target file can be searched out easily. 
         [0167]    While the present invention may be embodied in many different forms, a number of illustrative embodiments are described herein with the understanding that the present disclosure is to be considered as providing examples of the principles of the invention and such examples are not intended to limit the invention to preferred embodiments described herein and/or illustrated herein. 
         [0168]    While illustrative embodiments of the invention have been described herein, the present invention is not limited to the various preferred embodiments described herein, but includes any and all embodiments having equivalent elements, modifications, omissions, combinations (e.g. of aspects across various embodiments), adaptations and/or alterations as would be appreciated by those in the art based on the present disclosure. The limitations in the claims are to be interpreted broadly based on the language employed in the claims and not limited to examples described in the present specification or during the prosecution of the application, which examples are to be construed as non-exclusive. For example, in the present disclosure, the term “preferably” is non-exclusive and means “preferably, but not limited to”. In this disclosure and during the prosecution of this application, means-plus-function or step-plus-function limitations will only be employed where for a specific claim limitation all of the following conditions are present In that limitation: a) “means for” or “step for” is expressly recited; b) a corresponding function is expressly recited; and c) structure, material or acts that support that structure are not recited. In this disclosure and during the prosecution of this application, the terminology “present invention” or “invention” may be used as a reference to one or more aspect within the present disclosure. The language present invention or invention should not be improperly interpreted as an identification of criticality, should not be improperly interpreted as applying across all aspects or embodiments (i.e., it should be understood that the present invention has a number of aspects and embodiments), and should not be improperly interpreted as limiting the scope of the application or claims. In this disclosure and during the prosecution of this application, the terminology “embodiment” can be used to describe any aspect, feature, process or step, any combination thereof, and/or any portion thereof, etc. In some examples, various embodiments may include overlapping features. In this disclosure and during the prosecution of this case, the following abbreviated terminology may be employed: “e.g.” which means “for example”, and “NB” which means “note well”.