Perhaps your license lease has expired. Have you tried to open QV, then click File | Open in Server... and point to the server from where you are leasing your license? Open any document there - now your lease will have been
I think you need a named CAL for what you are trying to do, rather than a document license or a session license.
i am currently using a peronal edition qlikview, created some qvw files and put on a licensed server, and i am currently using a named cal leased from the server. when i call the qvw files on the server, it pops the above message.