Hello everyone,
I am having an issue with a clients network that started on 03/22 where RDP and RWW and Inbound emails stopped working. I applied available updates available at that time (listed below) and restarted the server. Functionality was restored until 03/25 and it stopped again in the middle of the day. I have confirmed that DNS settings are still correct for the domain including "remote.domain.us". These are the same settings applied at several other locations with the only difference being the domain and IP it points to. I have utilized "http://testexchangeconnectivity.com/" and the test passes without any problems for Exchange ActiveSync Connectivity and Inbound SMTP test. When sending emails after 4 hours a Delay email is triggered. After 48 hours a Undeliverable Queue Expired error comes back. I have confirmed that the Firewall is forwarding 25, 443, 987, 3389 to the SBS. Emails are sending out correctly. When doing the Microsoft Remote Connectivity Analyzer that message is received by the server but no other emails are being received. I have looked through the logs and noticed a few DNS errors related to unable to resolve Microsoft.com, I have made primary DNS on the SBS to its own address and secondary to the ISP provided DNS. I have also rebooted the server 2 times on 03/27 and 03/29. I have compared internal DNS settings and external hosted DNS settings to those of two other servers and all appears set correctly. I have also noticed before this happened on 03/22 that the daily Summary Network Report emails have been delayed or not coming to my external email account on a consistent basis. The only remote access I have to the server is through GoToAssist our VNC and RDP connections do not work. I would appreciate any assistance or suggestions that anyone has.
Updates Applied 03/22
Windows Malicious Software Removal Tool x64 March 2013 KB890830
Microsoft Exchange Server Standard Anti-Spam filter updates v3.3.12318.464
Update for Windows Server 2008 R2 x64 KB2806748
Update for Windows Server 2008 R2 x64 KB2791765
Update Rollup 4 for Windows Server Solutions Best Practices Analyzer 1.0 KB2796170
Update for Windows Server 2008 R2 X64 KB2786400
Platform update for Windows Server 2008 R2 x64 KB267083
Update for Windows Server 2008 R2 X64 KB2726535