Unlocker.rar -

The most popular choice for Mac users on the App Store . 2. Dealing with Locked System Files

A free, open-source alternative available on the 7-Zip Official Site . Unlocker.rar

Be extremely cautious when downloading any file named Unlocker.rar from unofficial sources. The most popular choice for Mac users on the App Store

If you are trying to delete a file that Windows won't let you touch, you don't necessarily need an "Unlocker.rar": you don't necessarily need an "Unlocker.rar":