I am a complete novice to FIM but am trying to set up the sync service to do a GAL sync between two AD forests. The forests have a two way AD trust in place and one is running Exchange 2010 and the other Exchange 2013. I have configured the two MAs and run a staged Import and a Sync on each. When I run an export though I receive an error saying that the "Required Attribute 'cn' is missing". Despite this the contact is created in the specified OU and does have a cn assigned. The proxyAddresses attribute is also populated as with all of the original users email addresses and the new contact shows up in Exchange as a Cross-Forest Contact. Can anyone suggest why I might be seeing this error, what implications it might have, and how to resolve it? So far I have seen the error when exporting from the Exchange 2013 domain into the Exchange 2010 one but not the other way around. I am using FIM 2010 R2 version 4.1.3419.0.
Thanks
Alan