Exchange 2013 in Child Domain

Hi

I have Exchange 2013 deployed on a Child domain. I log into the EAC using an account with domain admins in Child, Enterprise admins in Parent.

When I create a mailbox, it creates just fine in the Child Domain, but a message comes up in the side pane stating:

"The operation couldn't be performed because object <<GUID>> couldn't be found on <<Parent Domain DC>>"

Any advice?

Is this permissions related??

jk