Microsoft.Exchange.Data.Storage.StoragePermanentException - There was a problem accessing Active Directory

Recently we added some new hires to the system only to discover that when one of them tried to use OWA that an error was triggered - notably that there was an error accessing Active Directory and that the InnerException was Microsoft.Exchange.Data.Directory.InvalidADObjectOperatorException (see below)

Now this only happened with new users. Old users, ones we migrated from x03 to x07 could use OWA with no problem. I should note (and this is critical) that we still had our old x03 up, even though we had migrated all the old user mailboxes. This was because of our unified messaging needing to still run (for a wee bit) on a legacy system. A quick check on the hub server looking at the mailboxes verified my fears - the mailboxes had been created as 'Legacy' mailboxes.

How could this have happened? I checked with my cohort and he confirmed that when we created the boxes in AD he specified a storage group that was on the x07 server. A quick check verified this. Obviously when a new mailbox is created in a mixed environment (at least in ours) it defaults to the least-common-denominator - in this case x03.

The solution was fairly straightforward - move the mailbox. But how? It already WAS on an x07 storage group. Simple - move to a different storage group - voila!

Except.... it is still a problem...

DOH!!!

I peek into AD using ADSI Edit and discover that the mxExchVersion for the problem people IS NOT SET!!! A quick search brings me here -> http://support.microsoft.com/kb/941146.

Running the Set-Mailbox User_name -ApplyMandatoryProperties is the final step and everything is beautiful. OWA functions and the sun comes out.

On to the next quirk......