Just for completeness of the thread:
Please check your DA'ed addressbooks. Those derived from pernames.ntf are missing view Server\Mail Users. This view is needed for auto-populate. The reason is: update looks for auto-populate in all DA'ed addressbooks, not only the primary addressbook.
Possible solution: Copy over the view from pubnames.ntf to your addressbook. The error might be gone then, and the group members are auto-populated.
Just one more reason to not use personal addressbooks for directory assistance. http://www-01.ibm.com/support/docview.wss?uid=swg21420942
Feedback response number WEBBB2DKPB created by Dietmar Dumke on 07/05/2018