1. Log out of the web browser
2. Close the Eclipse client service completely
3. Relaunch the client service
4. Log back into the web browser
*If all users are experiencing this also check to see if the MSQL service is running. If not start, and it should (or do a restart) resolve the issue.
IF YOU ARE RECEIVING THIS ERROR AFTER A MIGRATION OR SERVER CHANGE:
Check that the old SQL instance name and the new one are the same. If not, you will need to rerun the SQL and Docstar installer. You can also change the dbo.companyinstance table in Astria_Host to reflect the new name.