I noticed an annoyance with an Exchange 2010 deployment with six servers (3 MBX and 3 CAS/HTS) where the servers had a hissy fit when the first MBX server was rebooted. The Exchange Management Console just didn’t want to connect whenever that MBX server was rebooted. It turns out that it relates to the value in the following registry key:
HKCU\Software\Microsoft\ExchangeServer\v14\AdminTools\NodeStructureSettings
The fix is to delete the key.
Enter our superhero saviour of the day – Captain Powershell – dah dah dah (fanfair).
Remove-ItemProperty -Path HKCU:\Software\Microsoft\ExchangeServer\v14\AdminTools\ -Name NodeStructureSettings
Just run that on each of your Exchange 2010 servers (see my post about backing up registry keys – what do you mean “you already deleted it”?).