Need to reinstall a deleted contact
Do you happen to know how it was deleted? Because there's actually two kinds of deleting - one is permanent, one is not.

Try the advanced search and turn on the option to search in the trash.



If they have been permanently deleted, then you won't be able to bring them back in the software - you'll need to find as much of the information elsewhere (backup of your database, emails you got from the system, etc) and manually recreate as much as you can.