Environment
Retain Unified Archiving 4.9.1
Situation
After upgrading to 4.9.1, when users try searching in the browse tab in Retain they are logged out of Retain.
Resolution
This appears to be a bug and has been reported to engineering.
The workaround is to make sure that there is a field selected to perform the search i.e. Mailbox, Indox, Sent items, Folder. etc.
Additional Information
This has been fixed for the 4.9.2 release of Retain.