sUBs

We'll have to use another tool then
Please download, install & launch reglite

Using Reglite, navigate to the key in question:

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Enum\Root\ LEGACY__11F*00DF*00E4*0006#*00B7*00BA*00C4*00D6`I

From the right pane, select - LEGACY__11F*00DF*00E4*0006#*00B7*00BA*00C4*00D6`I
Right click & select Properties.
From the Key properties page, click the "Take Ownership" button & exit the page
Then right click & try deleting the key