Issue: When you try to select a program to install, it is incorrectly listed as already installed.
Causes: Programs that experience issues during the installation or uninstall of a product may leave behind a registry key that could make the installer think the product is already installed.
You can run the Microsoft Fix it utility to scan the installer database and remove the errant registry keys. The utility is a Microsoft tool that scans the integrity of the installer database and corrects issues related to installations.
Fix problems with programs that can't be installed or uninstalled
If the utility has multiple entries for the product or an associated language pack entry, you will need to run the utility once for each entry.
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