maintenance update corrups WS?

Updated Creo Elements Pro 5.0 from M090 to M160. After that the local Workspaces got corrupted/could not be accessed. The error message was "Could not connect to the Server...". I had to uninstall M160 and reinstall M090 to get the WS back. We are using Intralink 9.1 M040.

Does one has to upload the Workspaces before installing a maintenance release?

Regards

Jan