Your server has stopped responding. Have you verified that the database is up and running correctly (you may need to restart both, make sure the DB is started first and up and running before starting the QC/ALM server app as this is required for the app server to server)? The ''communication security phrase'' is used to connect to and authenticate with the database.
What have you recently changed on the server that could cause this issue, such as expired a password (might have been done by IT, through group policy, or from security rules in place), patched the server, etc, as this can be a direct clue to what is happening on the QC/ALM server and what may have caused the issue.
Hope this helps,