Can I delete $Windows.~BT & $Windows.~WS folders after Windows 10 upgrade?

After you upgrade to Windows 10 you may notice two folders on your System or C Drive named $Windows.~BT and $Windows.~WS. These folders are created by Windows, during the upgrade process. The question now is – Is it safe to delete these $Windows.~BT and $Windows.~WS folders?

To see these hidden folders, Open your File Explorer to C Drive and under View tab, check the Show hidden files check box.


You will then see these two folders.

$Windows.~BT, $Windows.~WS

Right-click on these and select Properties. You will see that $Windows.~BT is around 625MB and $Windows.~WS occupies around 5.6GB. So deleting these would mean reclaiming a lot of valuable disk space.

Is it safe to delete $Windows.~BT & $Windows.~WS folders

$Windows.~BT and $Windows.~WS are temporary folders and can be safely deleted.

If you are unable to right-click on them and select Delete, you can use the following commands to change permissions and force-delete them.

Right-click on Start button to open the WinX Menu. Select Command Prompt (Admin).

Copy-paste the following and hit Enter to delete the contents of $Windows.~BT directory

takeown /F C:\$Windows.~BT\* /R /A 
icacls C:\$Windows.~BT\*.* /T /grant administrators:F 
rmdir /S /Q C:\$Windows.~BT\

Now copy-paste the following and hit Enter to delete the contents of $Windows.~WS directory

takeown /F C:\$Windows.~WS\* /R /A 
icacls C:\$Windows.~WS\*.* /T /grant administrators:F 
rmdir /S /Q C:\$Windows.~WS\

If this works, you will see a Successfully processed message.

delete $Windows.~BT & $Windows.~WS folders

If this does not work the first time, or you get maybe an Access Denied message, restart your computer and run these commands again.

If you get message “The system cannot find the file specified” it means the folder is already deleted.

If you need to delete more files and folders after the upgrade to Windows 10, you could search for Disk Cleanup, right-click on it, and select Run as administrator.

You will see an option Previous Windows installation. Check this option, see the other checked options and click on Yes. This will clear up 222GB of space. When you select this option, Disk Cleanup tool will delete the Windows.old folder as well as the $Windows.~BT folder, but not the $Windows.~WS folder.

previous installation

We suggest that you delete these two $Windows.~BT and $Windows.~WS folders, along with the Windows.old folder, only when you are sure that your Windows 10 installation is working fine, and you do not plan to restore or rollback your computer. Because if you do try to, you will receive a We’re sorry, but you can’t go back message.

Read next about the $SysReset folder.

Posted by on , in Category Windows with Tags
Anand Khanse is the Admin of, a 10-year Microsoft MVP Awardee in Windows (2006-16) & a Windows Insider MVP. Please read the entire post & the comments first, create a System Restore Point before making any changes to your system & be careful about any 3rd-party offers while installing freeware.