I have FME Desktop licensed on an air-gapped server but covid has changed my working patterns; so, for the 2 or 3 days I work from home I don't have access to my favourite software. Is there any way to borrow a license from my air-gapped server for use on a different network?
You will need a network connection to the license server to either borrow or return a borrowed license.
If you have a fixed license on the server there is not much you can do - If, however, you have a floating license set up then you can borrow the license for 2-3 days from within the network before you go home (assuming you're working on a laptop). After the time is up the seat will automatically become available on the server again.
The issue here is that it locks out a license from your colleagues for the whole time you're out of the office. Consider contacting Safe Software sales department to see if they are able to help with an interim solution.
The best solution would to have the floating licence server available somewhere which you can connect to via VPN.