Hi Brandon,
Jabber stores the credential when you input correct email address and password in local file, the credential file stored on %AppData%Roaming\Cisco\Unified Communications\Jabber\CSF\Credentials\ folder, could you help to check that folder not deleted when restart system please?
If that file not deleted or you didn't reset Jabber and the issue still reproduce, after Jabber startup could you send us a PRT report for further analyze? Here is how to generate PRT, Menu->Help->Reprot a Problem and it will generate a .zip file then send it to us.
Thanks,
Leon