UNIX/TS - which would become V7 could do uucp mail without Berkeley delivermail. And I believe there were versions of the delivery system around the Bell System system before TS -- maybe PWB 2.0 but I've forgotten. Anyone from Columbus or Indian Hill? delivermail - could handle the BerkNet, ArpaNet (on Ing70) and eventually UUCP. Then when Eric had to start dealing with the what he referred to as the header format of the day problem, he added a database production language -- and sendmail was born. I will just never forgive him for embedding the smtpd into it - I wish he had left it as a separate program like it was in the BBN tcp. Back to your question, I believe that local mail was around fairly early 3rd, 4th or 5th edition maybe. And uucp was spliced into it fairly soon their after, but I believe it was not the "default" mail code. Again, I think it was a few generations before the architecture of separation of the "Mail User Interface" , "Mail User Agent" , "Mail Delivery Interface" and "Mail Deliver Agent" into different components would emerge. And until such time, things are little blurry. Clem On Mon, Mar 13, 2017 at 8:47 AM, Warren Toomey <wkt(a)tuhs.org> wrote: