Using Treesize to monitor big folders in Windows and guess what C:\windows\system32\config was 4,2 GB It contained thousands of Drivers{guid} files In explorer you don't see them, even when hidden files are checked to show Googled around and found a powershell option cause elevated prompt could not find the files Just want to share with those who have the same issue with their config folder execute in powershell $SysConfigFiles = (Get-ChildItem -Path "C:\windows\System32\config" -Filter * -Hidden) $SysConfigFiles | Measure-Object $FilesToDelete = $SysConfigFiles | Where-Object {$_.Name -like "DRIVERS*"} $FilesToDelete | Remove-Item -Force This did the trick for me, and my config folder is 426 MB again