Within the last week definitely, not sure the exact day, our SBS 2011 started behaving badly (it has been in continuous operation for almost 3 years). I only noticed the issue when I had to add a user to a group. I logged into the SBS, with a Domain
Admin Account, to make the change. I could not connect to the ADUC MMC nor could I use the Server Console (which sucks and fails constantly BTW). Consequently, Exchange is also having issues, although almost all of the Exchange functionality still works (albeit
sporadically), except for backend management. Basically the error states that the server is not operational when it is.
So, I rebooted the server, now on my third try. The Event Log is not showing anything in particular, but maybe I'm not digging far enough. When I try to run a DCDIAG (a full test from the DC I normally run it), I get the error 81 message.
When I do a DCDIAG check to make sure it can connect and see the folder shares, it can. I looked in DNS and everything appears OK. ADSI Edit runs fine, my secondary DC runs fine. The Firewall is allowing the required ports (both the Win Firewall,
which is off, and the Trend Firewall, which is on) I meant to check on the replication status on our secondary DC, but failed to do that, but will update when I get that info.
Services are all running, and even when I select to connect to a different DC, the failing DC does show up in the list as Online and is selectable. Once selected, ADUC fails again. Best Practices analyzers fail because it cannot connect to the
DC.
No changes have been made to the infrastructure for over a year except for deploying TFS about 6 months ago. The server is regularly updated every 2 weeks and reboot. The only other 3rd party updates that may have happened on my last update day
would be the Backup Exec Agent, but I don't think that would have caused this (but maybe).
Any ideas would be greatly appreciated, this is a head scratcher for me. Everything indicates that things should be operating within normal parameters.
