Source: http://eznec.com/old_versions.htm
Timestamp: 2019-04-20 22:48:07+00:00

Document:
Older versions of EZNEC usually can be run on modern systems. However, some accommodations must be made. But computers and operating systems have changed a great deal since most earlier versions were developed -- v. 3.0, 4.0, and 5.0 were last sold in 2004, 2007, and 2015 respectively. The current version of EZNEC is updated as needed to achieve and maintain complete compatibility as systems evolve, but older versions are not. Consequently, a number of problems can occur other than those described here, the only solution to which is an upgrade to the current version.
Replacement CDs or downloads of EZNEC v. 3.0 and 4.0 are no longer available. Please see "Upgrading to v. 6.0", below, for upgrade information. Replacement v. 5.0 CDs (only) are still available -- see this page for v. 5.0 reinstallation and CD ordering instructions.
The number of false positive virus reports has been steadily increasing for various files in all versions of EZNEC, including ones which have been in use and unchanged for many years. Web research shows that this is also affecting many other programs. (Search, for example, "false positive virus", without the quotation marks, with Google.) The cause is that anti-virus programs now include "heuristic" detection methods which use proprietary routines that attempt to detect unknown viruses rather than identifying known malevolent code. There also seems to be an effort in this competitive market to have a product "find" more "viruses" than competing products. The result is a large and increasing number of false positive virus warnings.
EZNEC v. 6.0 has been modified to reduce the number of false positive indications, but earlier program versions are more susceptible. Problems particularly occur during installation, but also sometimes during download or when running the program. Anti-virus programs should always be disabled during installation. If there is interference with the program itself, an exception must be made for EZNEC or, if that isn't possible, the anti-virus program must be disabled when running EZNEC.
NOTE: I've received several reports that McAfee and some other anti-virus programs might still be active even when "disabled", and that uninstalling it can be necessary to truly disable it. Alternatively, EZNEC installation can be done in Windows Safe Mode.
All versions of EZNEC require you to have Administrator privileges for installation.
It's very important to disable anti-virus software when installing EZNEC. Anti-virus programs often give no indication that they are interfering, and the result is an incomplete installation. See the section above for more information. If it's not possible to disable anti-virus software, you might be able to install EZNEC in Windows Safe Mode, where anti-virus and similar software won't be loaded. See Windows documentation for instructions on starting the system in Safe Mode.
EZNEC v. 3.0 and early revisions of EZNEC v. 4.0 cannot be installed on 64 bit operating systems, except under the XP Mode available in some versions of Vista and later Windows systems. An updated, 64 bit compatible v. 4.0 installer might still be available -- contact w7el@eznec.com if you need one. V. 3.0 can be installed and run only under the XP Mode -- see your Windows documentation for instructions.
The default installation location for EZNEC v. 5.0 and earlier is under C:\Program Files\ or C:\Program Files (x86)\ and these versions write some files to their own directory. Windows Vista and later systems often have file permissions which prohibit writing into the Program Files directory or subdirectories, causing EZNEC to crash when it tries. The easiest solution is to create a directory directly under the root, for example C:\EZNEC\, and install the program there. EZNEC v. 6.0 doesn't write any files under C:\Program Files [(x86)]\ so doesn't have this problem with file permissions.
"Installation parameters have become corrupted"
If this message appears when the program is started, the reason is almost always an incomplete installation caused by anti-virus software. Please see the above section for more information.
"Core part of EZNEC has quit working "
This message usually appears when you attempt to open certain windows. It's caused by a Windows "feature" called Data Execution Prevention (DEP) and affects EZNEC v. 5.0.50 and earlier. It's necessary to either turn off DEP or make an exception for the main EZNEC executable file EZW.exe (or EZWpro.exe with Pro program types). Here's the procedure for Windows 7. It's similar but slightly different on other systems -- a web search of 'DEP vista' for example (without the quotes) will yield detailed instructions for other operating systems.
Setting DEP on Windows 7: Open the Control Panel. If it's set to View by Category, select System & Security, then System; if set to View by Icon (small or large), select System. Then choose Advanced System Settings on left, and click the Settings button in the top (Performance) section. Choose the Data Execution Prevention tab at the top. The two choices are "Turn on DEP for essential Windows programs and services only" (basically disables DEP) and "Turn on DEP for all programs and services except those I select". Selecting the first option will fix the problem. Or, if you want to retain DEP for all programs (the second option), click the Add button, locate EZW.exe in the EZNEC v. 3.0 program directory (C:\Program Files\EZW if you chose the default during installation), and add it to the exception list. Click Ok and Ok to finish, and reboot.
"Error 75: Path/File Access Error"
A crash with this message can occur frequently or infrequently at various times when running the program. EZNEC v. 5.0 and earlier programs write some files in their own directory. File permission settings on some systems have been set to prevent programs from writing into the C:\Program Files directory or subdirectories, so this crash occurs when EZNEC has been installed in the default C:\Program Files\EZW directory. The simplest way to solve this problem is to uninstall EZNEC, create a directory directly under the root, for example C:\EZNEC, and reinstall EZNEC there.
All users who purchased an earlier version of EZNEC are entitled to a substantial discount from the full price when upgrading. To upgrade via the web, you'll need your Customer ID number which was sent by email or mail shortly after v. 6.0 introduction. If you want to upgrade and don't have your Customer ID number, email w7el@eznec.com to request it. Please don't purchase a new program at full price and request a refund.

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