Emails wait in the Internet Mail SMTP Queue. The delivery process goes through the "advanced queue --> categorizer --> remote queue submission" sequence a couple times and then sends out he email after 3 hours. The packet capture shows a lot of syn/ack traffic between the Exchange 2003 server and the SmartHost (McAfee email appliance) while the messages are queued up. Looks like the SmartHost is waiting but the Exchange server doesn't send or the Exchange server wants to send but the SmartHost doesn't want to accept while the messages are delayed in the queue. What gives?
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