Make sure the user has inherited permission granted to domain\Exchange Servers to allow List, Create child, Delete child of object type "msExchangeActiveSyncDevices" and doesn't have any deny permissions that block such operations.
I've already added exchange server to the user permissions and granted Create and Delete "msExchActivesyncDevice Objects" and I'm still getting this crappy error message.
It looks exactly the same as other users that can get email on their phones, which is what this user can't do.
any suggestions ?
Server 2012 R2 and Exchange 2013