Browser Timeout

Whenever I try logging in from browser and Classic, System throws out the error "Connection timeout or invalid message type returned from JMS queue.". This locks every User that tries to log in to the system. Locked users are released from DBTools but when tried again, the user gets locked.
I have restarted server and jboss on a couple of times but the issue still persists.

Can i please get help on this? Thanks in advance

Check the Server.log file to see what is the Error.. Easiest way would be to try to do the same in classic mode from the TAFJ Shell prompt by executing tRun EX and trying to login..
Could be license issue, some fatal error, some missing file etc will be shown on the screen itself

could you share log and screenshot from classic,
if you are using mssql try restart db it could be db lock contention;
regards