Any time you make a MIMESweeper policy change, the MSW services on the Policy Servers (PS) will stop and start. Sometimes, when saving changes to the policy you may find the security service on a PS goes into 'Stopping' and gets stuck there. And unless you babysit your MailSweeper system or permanently have a copy of the System Health page open, this might go unnoticed for a while and you can end up with big queues of messages and angry users.
System Health will show you the server with the problem. Rebooting your PS fixes it in the short term, but it will happen again unless the cause of the problem is fixed.
The failure is due to corrupt messages in the analysis queue. When your system is healthy, on the Message Center page under Message Queues - "Waiting for analysis (Analysis)" should normally be zero. During very busy periods or if your PS is struggling it may vary between 1-5 but generally you should not have anything queued for analysis. If you ALWAYS have 1 message queued here then this is telling you the Security Service is unable to process a message in this queue. Using the MSW Manager stop the Receiver Service and Security Service on your PS and remote on to it. Find the queue in your file system (E:\Program Files\Clearswift\MIMEsweeper for SMTP\Mail\Queues\Content Analysis\Normal), in there you can normally see the .RCP and .MSG pair causing the problem - it should be the oldest files in the folder. Try and open the .MSG file, you should see header information and other stuff, but if you just see garbage and symbols then you have a corrupt message on your hands. Removing the message pair from this folder and starting the services again will fix your problem.
