An IIS directory entry couldn't be created. The error message is Access is denied.
. HResult = -2147024891
+ CategoryInfo : NotInstalled: (PER-EXCHMBX\Exchange (Default Web Site):ADObjectId) [Get-OwaVirtualDirecory], IISGeneralCOMException
+ FullyQualifiedErrorId : EBEB5204,Microsoft.Exchange.Management.SystemConfigurationTasks.GetOwaVirtualDirectory
For example here we have an Exchange 2010 shell and an Exchange 2007 shell. We can see the Exchange 2010 shell cannot access the Exchange 2007 servers... where the Exchange 2007 shell is fine.
To allow the Exchange 2010 shell to connect to the Exchange 2007 servers you must add "Microsoft Exchange Security Groups\ Exchange Trusted Subsystem" as a local admin to all Exchange 2007 servers.