Ever since last Friday when our Mail Server was flooded with SoBig.E viruses I have had the following problem. The server will run fine for 24 hours then will no longer process attachments. The users get a message "cannot open attachments. I then reboot and everything is fine again for about a day. I have Exchange 5.5 with SP4 Running on a Windows 2000 SP3 member server. We are running E-trust version 7 as our Antivirus Solution. Has any one seen a similar problem? The server has a lot of free disk space (25 gigs or so) so I don't think that's the problem.