msizap.exe reports No product/patch data was found

I would highly recommend not using msizap on your computer. Microsoft has retired the Windows Installer Cleanup Utility, which included msizap. See Microsoft kb2438651 for more information, specifically this portion of the kb article:

Important: The Windows Installer Cleanup utility (MSICUU2.exe) that was previously referred to in this article has been retired. While the Windows Installer Cleanup utility resolved some installation problems, it sometimes damaged other components installed on the computer. Because of this, the tool has been removed from the Microsoft Download Center. The Program Install and Uninstall troubleshooter is a replacement for that utility.