This can also happen if the HANSA.HDB is renamed, and the service is started back up. It creates an "empty" HANSA.HDB which is not set up for remote access, and the client gets that message.
Hello,
We also have a customer on windows who is on 2026-02-28 having the exact same error message after updating.
The title of the messagebox is in our case is: "C:\Program Files(x86)\Han...