AD operation failed error on stock Exchange 2010 server

Hello all

I downloaded Exchange 2010 SP1 and SP2 and from the folder tried to install SP1

I get the following error:

The following error was generated when "$error.Clear():initialize-ExchangeUniversalGroups -DominController $RoleDomainController -ActiveDirectorySplitPermission $RoleActiveDirectorySplitPermission

"was run: "Active Directory operation failed on some-server.com One or more attribute of the object 'CN=Organization Management,OU=Microsoft Exchange Security Groups,DC=some-server,DC=com' already exists

I have tired running setup.com /ps using command line in the Service Pack 1 directory and get an error about mailbox role.

Googles and got no joy.  

Can anyone help.

Thanks