ArcGIS Server 10.1 Windows Domain User store crashes

Discussion created by yguan13 on Oct 25, 2013
Latest reply on Feb 5, 2015 by mmdolbow
This has happenned twice in the last 5 months since I installed ArcGIS for Server 10.1. I use "Windows Domain" for User Store, and "ArcGIS Server Built-in" for Role store. The authentication tier is GIS Server. This morning, the AGS server seemed to lose the connection to Windows Domain (AD). I can not login the Manager with my Windowss credential. Fortunately I have not disabled the primary site admin account yet so I logged on using the primary site admin. But inside the manager, I can not access the "Security -> User" tab.  I tried restarting the AGS server, rebooting the server, no help. But after I reset to User Store back to "ArcGIS Server Built-in", and reset it back to "Windows Domain", everything started to work fine. Anybody know why? I definitely do not want this to happen again.  I am at ArcGIS for server 10.1 SP1.