SBS 2008 running as a VM on a Windows Server 2008 Hyper V host. After a reboot, the SBS 2008 VM comes up but not all exchange services start, namely Information Store and System Attendant. I've already tried Methods 2-4 in http://support.microsoft.com/kb/940845 and most of the methods break the services so they won't start. I had to restore registry keys and reboot just to get them to start. I also applyed Exchange 2007 SP1 Rollup 9 Update and the issue still persist.

Normally Information store and Sys Attandant service are heavily dependendent on AD. Make sure your AD (including DNS) is in healthy state.How about AD topology discovery service? Is it coming up fine?Raj

Do you see any kind of below events? Exchange Server 2007 managed code services do not start after you install an update rollup for Exchange Server 2007 Also run EXBPA and make sure no issues with REG key values. Also try posting under SBS Forum to get help from sbs experts https://connect.microsoft.com/sbs08/community/discussion/richui/default.aspx?wa=wsignin1.0Vinod |CCNA|MCSE 2003 +Messaging|MCTS|ITIL V3|

also try to stop the the third party application (Anti Virus etc) and then reboot the Box.Raj

You're running in a VM, it may mean that networking is coming up slower than it would on a physical box. As noted previously AD needs to be up and running and that may be slower to start on a VM. You can configure a time lag on the service startup for the exchange services, or set the dependencies to ensure other prerequisites are already up.