event log level set to EXPERT and yet i see event id 9320

I Run the Command :

set-eventloglevel -Identity "MSExchangeSA\OAL Generator" -Level EXPERT -verbose

then i restart the Microsoft Exchange File Distribution service and right after run the command :

Get-OfflineAddressBook | Update-OfflineAddressBook

and i get the log:

OABGen could not generate full details for some entries in the offline address list for address list '\Global Address List'.  To see which entries are affected, set event logging for the offline address list generator to at least medium.

this is the only warning i get and i add to the default domain controller the exchange servers group to the Manage Aduiting and security log