Windows Patch Files are used to store important information about applications installed using the Windows Installer. Every time you install or update an application, an installer and a patch file are created inside a hidden directory in Windows, eg. “C:\Windows\Installer".
These files are required if you need to update, patch, or uninstall the application in case you need to roll back the system to a previous version. However, these files do tend to grow in size and become outdated as the software can consume gigabytes of storage, thus you can safely remove some patch files to free up disk space (though it may produce some strange behavior when trying to update that program). There are a number of software programs available that can help you remove these Windows Installer Patch Files.