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Unable to locate the installation log file WFXUNIST.ISU

Error message: “Unable to locate the installation log file C:\Program Files\WinFax\WFXUNIST.ISU” during WinFax PRO uninstallation or “WFXUNINST.ISU is missing or corrupt.”

This is an error that causes an uninstall of WinFax PRO to fail.  This file is an un-installation log file that is generated by a third party installation tool called Install Shield. Its automatically generated when you first installed WinFax PRO, so you won’t find this file on the WinFax PRO installation CD ROM. This log file contains all the information and settings that the uninstall program requires to remove WinFax, such as the program folder locations and features that you added or removed during the install process.

The problem is if you don’t have this file, or it is bad/corrupt, you won’t be able to successfully uninstall WinFax PRO.  The uninstall halts, and you can’t continue. You’re left with WinFax that may be partially installed.

Possible Solutions:

If you have an installation of WinFax on another working computer, you could copy the WFXUNIST.ISU to the computer where the problem is occurring.  However, both computers must be using the same folders and features.  If you installed the software in the same way on both machines, to the same folders, then this may  solve the problem.

The preferred solution is to reinstall WinFax PRO to the same installation folder, so the uninstall log file is recreated and any corrupt or missing files are recreated.  You should then be able to perform a proper uninstall after you’ve reinstalled successfully. We always recommend making a backup of your entire WinFax folder including any Data folders before attempting this if you require any WinFax information.

NOTE: WinFax PRO versions 10.02 and 10.03 also require that you must uninstall before you can reinstall the software, so the above method will not work for these versions as it will display a message that an existing version of WinFax is installed, and it will halt the install process. Since you can’t uninstall, you can’t reinstall.

If you are a premium support subscriber, we have our own tools available within our WinFax Tools program and in our premium download area to bypass this message and allow an install overtop the existing version.

Another option is to bypass the WinFax PRO uninstall completely and use the WinFax Clean utility, available in the Premium Downloads area. This program will completely remove WinFax and all related registry keys.