I am NOT the super tekkie on this forum. BUT, I experiment and survive. :) The important addressbooks are abook.sqlite and history.sqlite. From my experience, you can delete all the others (when thunderbird is not running) and the appropriate ones will be recreated when you restart thunderbird. That's been my experience and I just did it prior to writing this response. Also, if you still have abook.mab or history.mab, they are old and can be deleted

Thanks David. I was thinking along the same lines, just didn't want to risk corrupting Thunderbird by blindly going ahead, just in case. I do have daily backups, but it's a lot less stressful if you can be fairly certain what you are doing is not going to cause problems. Appreciate the helpful reply.