From Web Intelligence Error Messages
Web Intelligence Java Report Panel (WIJ) Error Messages
Unexpected error. If you cannot reconnect to the server, close WebIntelligence and start again. (WIJ 20002)
The server may be down or your user session may be closed.
See your BusinessObjects administrator.
When the WIJobServer process gets this error, it usually means the repository (CMS) database is unreachable for several minutes (backups often cause this), it causes instability in many of the core BO XI Services.
If you log into CCM on the server(s) and restart the WebIntelligence Job Server process, it clears these errors up. This is often easier than rebooting the entire server, especially if BOXI is not the only application running on it.