PatchCleaner is a free tool which can detect and safely remove junk files from the \Windows\Installer folder, potentially freeing up gigabytes of hard drive space.

The folder contains Windows Installer-based setup programs and patch files, and uses these whenever you want to modify or update the software. They should be removed when you uninstall a program, but guess what? This doesn’t always happen.

Launch PatchCleaner and it first uses WMI to obtain the official list of Windows Installer-based programs and patches.

The program then scans your \Windows\Installer folder, identifies installers and patches which don’t appear on the WMI “installed” list, and identifies these as “orphaned”.

Browse the patches installed on your PC and see how much disk space they take

This is not a foolproof system. The developer reports that “there is an issue with the way Adobe Reader patches and updates, where PatchCleaner will remove required patch files”. He’s addressed this by building a filter system which enables ignoring Adobe or any other applications you like, but it does illustrate that the program can make mistakes.

Fortunately, once the scan is complete PatchCleaner offers to move files, rather than delete them. That’s definitely our preferred option, as if you notice problems with an application, you can easily copy the files back.

We’ve seen reports of people recovering gigabytes of drive space using PatchCleaner. It “only” freed up 312MB on our test Windows 10 laptop, but that’s still worth having, and not something we could easily achieve with standard cleanup tools.

PatchCleaner is available for Windows Vista and later.