Error in Order Entry

Hi 

A client is trying to change the Quote Number in Order Entry Options, which they do every month but this time they receive an error message.

Everyone is out of Accpac at the moment, but the error they receive is "Incorrect Procedure. You cannot update Order Entry options until all other users have left Order Entry and all other Order Entry windows are closed."

There is nobody in Accpac and no windows are open. This client started using CRM yesterday, not sure if this is an issue?

Thanks