If Disk Cleanup is not working properly and does not remove Windows Update files, Temporary files, Windows.old folder, Internet files, etc. do this to fix the issue. Remove Temporary Files ...

Disk Cleanup is a built-in Windows utility to help you free up space on your computer’s hard drive. It can clean up downloads, temporary internet files, recycle bin, and even system files.

“I used Disk Cleanup to delete Windows Update Cleanup files as they take up almost 9GB of space. Even after using Disk Cleanup Utility, it still shows that they haven’t been cleaned.