We have been fielding numerous reports from customers complaining that their email has simply disappeared over the last few days. Either mail sent directly to them, or quarantine reports or anything suspicious.

Over the past two days we have been able to identify two causes of this on target Windows 2003 servers running Trend Micro or IMF. As you may be aware, Exchange team had a brief pause in IMF updates (few weeks) and the most recent update that was pushed out is far more aggressive than the previous ones. It is likely that if you do have IMF installed it is either archiving or deleting messages. In Trend’s case, messages are simply disappearing.

To identify if this issue is affecting you please turn on message tracking and try to search for messages you know you should have received. You will likely see “Message sent to categorizer” at which point there is no further information on the message. With IMF you will see a report by IMF indicating that the message was either deleted or archived by IMF.

These issues are totally unrelated to ExchangeDefender but they will impact the performance of clients that use both for protection. As always, please uninstall/remove/disable mail hygene products to troubleshoot the core of the problem. We have facilities to help you find out if ExchangeDefender is at fault, if you suspect it please call (877) 546–0316