"And I have found one more probelm. After restart the Microsoft Forefront TMG Control service stays off and I have to start it manual"
Hi Martin,
Try setting the service IsaManagedCtrl ("Microsoft Forefront TMG Managed Control", not to be confused with "Microsoft Forefront TMG Managed Control") to startup type "Automatic (Delayed start)". No other Exchange/TMG services to delayed start. That worked for me so I don't have to start manualy. I even tested setting back to regular automatic, and it fails again.
But the annoying 31506 error keeps logging.
This time I can't find anything missing in the e-mail policy configuration that was meant to be applied to the edge server.
So I guess it means nothing in my case after all, and I have to find other ways to get incoming mail past the edge.