Msizap.exe is a command line utility that removes either all Windows Installer information for a product or all products installed on a computer. Products installed by the installer may fail to function after using Msizap. On Windows 2000 and Windows XP, administrative privileges are required to use Msizap.exe[^1^] [^2^].

This tool is only available in the Windows SDK Components for Windows Installer Developers and should not be redistributed. Use the recent version of Msizap.exe (version 3.1.4000.2726 or greater) that is available in the Windows SDK Components for Windows Installer Developers for Windows Vista or greater. Lesser versions of Msizap.exe can remove information about all updates that have been applied to other applications on the user’s computer. If this information is removed, these other applications may need to be removed and reinstalled to receive additional updates[^1^] [^2^].

To download Msizap.exe, you need to install the Windows SDK Components for Windows Installer Developers from here. After installing the SDK, you can find Msizap.exe in the bin folder of the SDK installation directory.

To use Msizap.exe on Windows 7, you need to run it as an administrator from a command prompt. You can use various options to specify what you want to remove, such as product code, MSI package, or all products. For example, to remove all information for a product with a specific code, you can use this command:

msizap T * [WA!] {product code}

For more details on the syntax and options of Msizap.exe, you can refer to this article or type msizap /? in the command prompt.

Be careful when using Msizap.exe as it can cause irreversible damage to your system if used incorrectly. Make sure to back up your registry and data before using it. Also, do not use it on products that are still functioning properly or that you want to keep on your computer.

Msizap.exe is useful for cleaning up the Windows Installer information that may be left behind by some uninstallations or failed installations. This can help free up disk space and improve the performance of your system. However, Msizap.exe is not a replacement for the standard uninstallation process and should only be used as a last resort when other methods fail.

Before using Msizap.exe, you should try to uninstall the product using the Add or Remove Programs feature in the Control Panel or the uninstaller provided by the product itself. You can also use the Windows Installer Cleanup Utility (MSICUU2.exe) to remove the Windows Installer configuration information related to the product. This utility is available from here.

If none of these methods work, you can use Msizap.exe to remove all traces of the product from your system. However, you should be aware of the risks and limitations of using this tool. Msizap.exe does not check for dependencies or file usage before removing files or registry keys. This means that it may remove files or registry keys that are shared by other products or that are still in use by your system. This can cause other products to malfunction or your system to become unstable. Therefore, you should only use Msizap.exe on products that you are sure are not needed or used by any other products or processes on your system.