Contacts: "Some server contacts could not be copied..."

On MacBook Pro, in Contacts, iCloud account throws the warning: "Some server contacts could not be copied to this address book."

How can I determine which contacts are not synched?

How can I clear the warning and be confident that Contacts on the MacBook are mirroring the iCloud list?

This is a sudden problem, appeared yesterday without obvious change in OS or application environment. Previously had been operating normally. Problem appeared after adding a contact from Mail, using "Add to Contacts" tool.

Contact entries synch properly across my other devices: iMac and iPhone. All are logged into the same Apple ID. The web iCloud Contacts list shows five more entries than Contacts on MacBook Pro. The count on the web matches the count on my iMac desktop machine. Contacts on iPhone appear normal.

I have disabled and re-enabled the iCloud account on the MacBook, and restarted both the application and the machine, per the Support page procedure. iCloud is the default Contacts account.

Clue: on the MacBook console, system.log shows in part: Contacts[1590]: [CardDAVPlugin-ERROR] CardInfoFromVCardData(): Ignored vCard Theresa Stevens:/1400709384/carddavhome/card/NzFENEFBNUQtNkMyRi00QkU5LUJDODItRkRBMDAyND g4RTI2.vcf because ABPerson create failed. VCard: "BEGIN:VCARD... with details of one VCARD. That person is not in my iCloud list or any other list.

MacBook Pro is 15-inch, early 2011, 8GB RAM, Intel Core i7, OS X 10.10.3

Contacts is 9.0