Could some problems of ‘lost’ addresses in Mail result from failure to migrate the ‘previous addresses’ which are stored by the Mail app?
Contacts
I have been trying to use Contacts to build a list of potential clients. Often, several work for the same company, but Contacts insists that I create each card from scratch. Is there any easier way?
Contacts launches but hangs when I try to use it.
The Eclectic Light Company 