You May receive an Error when Exchange 2010 is installed and you want to remove an Exchange 2007 Mailbox Role!
Mailbox Role Failed
Object is read only because it was created by a future version of Exchange: 0.10 (184.108.40.206). Current supported version is 0.1 (8.0.535.0).
A closer look at the ExchangeSetup.txt tells me something about the Offline Addressbook and Public Folder store:
[28/10/2009 21:37:05]  Checking whether the public folder database "MB\Public Folder Storage Group\Public Folder Database" has local replicas.
[28/10/2009 21:37:06]  Searching objects of type "OfflineAddressBook" with filter "(PublicFolderDatabase Equal MB\Public Folder Storage Group\Public Folder Database)", scope "SubTree" under the root "Delimon Organization".
[28/10/2009 21:37:06]  Previous operation run on domain controller 'x.delimon.be'.
[28/10/2009 21:37:06]  [ERROR] Object is read only because it was created by a future version of Exchange: 0.10 (220.127.116.11). Current supported version is 0.1 (8.0.535.0).
Opening the Offline Addressbook settings with Exchange 2007 Management Console also spawns the same error:
And makes the configuration Read Only
So lets remove the Exchange 2007 CAS Server from the AOB Distribution and disable Public Folder Distribution with the Exchange 2010 Management Console…
That did not change anything :(
So lets remove the Public Folder Database with ADSIEDIT.MSC
(Connect to the Configuration Container)
IMPORTANT : You must have moved all PF data to another server, this will destroy your PF Database.
(In my case all information was already moved)
Now that replication has finished you can see that the Public Folder DB is no longer available
So now let’s retry the uninstall…
That worked out great :)
You can see below that the Exchange 2007 Mailbox Server has been removed from the Exchange Configuration
If you have a public folder on your mailbox server then the Uninstallation of Exchange 2007 Mailbox Server may fail if Exchange 2010 is already deployed.
My guess is that Microsoft will release an update installer/uninstaller that does not fail on the Offline Address book/Public Folder info that was upgraded to Exchange 2010 version information in AD
Using ADSIEDIT.MSC should not be considered a supported solution, this is only a workaround!