What is the $WINDOWS.~BT folder in wiindows 10 after update ?

[Windows Central Question]

After the Windows 10 update There is a folder named $WINDOWS.~BT on the root of my C:\ drive. It is a hidden folder and is 3.34 GB in size.

What is its purpose? Is it safe to delete it?

 

[Daniel Gilbert M]

That is the folder in which the downloaded ISO of W10 update was extracted and used during the upgrade time ....
You can use disk cleanup utility to delete those files. (Just open start and type "Disk Cleanup")
If you have upgraded already, then its safe to delete.
However if you keep them, and you have other machines (which need the W10 upgrade) on the same network, then these files will be used for the upgrade process. (So you don't need to download the whole update again on the machine to be upgraded)