I have also verified the ~/Library/Containers/com.apple.AddressBook folder is also involved as it gets updated when a change is mode to the Contacts List.
That folder includes
a link to ~/Library/Application Support/Address BookI also ran into a reason why replacing the ~/Library/Application Support/Address Book folder replacement may have failed in MG2009's case. When Contacts launches, if ~/Library/Application Support/Address Book folder is not present Contacts immediately creates the folder and structure with two entries Apple and the User. (Sound familiar?) When I restored the ~/Library/Application Support/Address Book folder I received no warning the folder was being overwritten and instead the restored folder ~/Library/Application Support/Address Book 2 was created. (I haven't figured out why I wasn't offered the overwrite option?) After a moment of panic when my Contacts list was not restored 😱 After discovering the renaming instead of overwriting, I corrected the folder names and violà the contacts list was restored. ðŸ˜
If I followed that, you're postulating that MG2009's drag & drop may have actually worked but he was launching the wrong Address Book?
Hah! Sounds all too plausible.
Since this hasn't come up, it's worth mentioning that every time I update Contacts I hit File > Export > Contacts Archive, and a backup appears in ~/Documents. Having followed the same practice would have saved MG2009 a heck of a lot of trouble.
