My client has an Exchange 2007 server and Outlook 2007 client. Every now and then individual emails will disappear from his inbox or other folders. It's very rare but frequent enough to be a problem. I've checked all views and filters and they are fine. He is the only user among 35 who has this problem. He can have the email in a folder for 3 weeks and then go look for it and it's gone. It happens about once every couple of weeks. All Antivirus scanning etc... happens prior to email being handed off to Exchange. Any thoughts?