You might be wondering what’s the difference between Windows BT folder and Windows WS folders. As you can guess, the previous installation folder will help you downgrade the Windows 10 machine to its previous version if you don’t like the new version or if it is creating problems. For instance, when you upgrade from v1090 to v2004, these folders are automatically created with all the files relating to your previous Windows installation. $WINDOWS.~BT and $WINDOWS.~WS folders are created when you upgrade from one Windows version to the other.
Let me show steps to delete $WINDOWS.~BT and $WINDOWS.~WS folders in Windows 10. Deleting these folder will instantly free up a ton of space. If you are running out space on your hard drive or don’t like wasting that much of space then you delete Windows BT folder and delete Windows WS folder for good. As you can guess, that is a huge amount of space to be spared. Typically, the size of these folders will be anywhere from 15GB to 40GB depending on your system.
