What are the setting for the vcs package (VCS-Configure) for the get mode, restore and working directory. Also do you have sessions tied to projects (Project-properties-options tab). Could this have something to do with the project you change to having files open that have been checked out by someone else since that project was closed?
No, it is not the message mentioned in reply 3.
When I change the project thru the menu botton "project view.Open Procect" ME first closes ME and tries to start a new session. At that moment I receive the attached message (in german..) crash_message.jpg