MDT Professionl Edition enables to borrow floating license. This allows to use MDT without connection to license server. Borrowed license may be returned to the server at any time, which will result in unblocking the license.
At the beginning you have to start MDT License Manager tool.
Select License Details tab. In licenses table select borrowed license.
Click Return License button.
Confirm license return by clicking Yes in message box.
License has been returned to server.
New license status indicates the license has been returned.
Verifying Active Licenses
Borrowing Floating License