NX Witness server (Windows) has lost its configuration after an update

Today NX Witness found an update for its client and server apps and installed them. The update was triggered via the Mac client for both server and desktop client. The server is a Windows 11 machine.  The server update never finished in the Mac client, so I eventually clicked "finish" and it went on to do the desktop app. 

 

Afterwards, the server has forgotten its settings and is asking whether I want to set up a new server or add to an existing system. If I put in the existing system details (localhost:7001 and my old admin username and password) it doesn't recognise them. 

 

Any suggestions on how to rectify?