Since late yesterday afternoon my Exchange 2003 sever has been problematic. The OWA client frequently lost connection and would have to re-authenticate. Looking at the event log I found repeated error messages, event id 7031 and 7034. Basically IIS Exchange Admin repeatedly restarted multiple times, SMTP service repeatedly restarted multiple times, and Exchange redirector repeatedly restarted multiple times.
 I searched Microsoft’s knowledge base but was unable to find anything that pertained to my configuration of server and OS. It was not an issue with disk space because there was plenty, nor was it memory. Exchange service pack 2 had been applied months ago to increase the database size from 16G to 75G, as we had out grown the 16G limitation. After much searching on the internet, I came across an article that stated it may be a problem with the Symantec Antivirus Spam filter. I had installed Symantec Antivirus for Exchange version 5.0.2.221, with Premium Anti Spam many months ago. I stopped all Symantec Antivirus services and cleared all event logs. After monitoring the logs, it seems that the problem went away, the cause was definitely the antivirus and spam filter.
I called Symantec technical support, after being on hold forever, I was connected with a support technician. After explaining the problem and symptoms, I was informed by the tech that this was a known issue with Premium Anti spam. The problem first surfaced in December 2006, they have released a new version 5.0.5 to fix this, but the fix did not work for all. For those who the fix does not work, there is a work around solution, it means editing and deleting lines in file. I will post this file later. But in the meantime I am trying to download the new version and cannot do so because I have to apply for a new license number first. I was then transfered to the license department, after staying on hold for over 15 minutes, I hung up the phone. I will try calling them tomorrow, had enough of waiting next to a phone for one day.