Author: Greg Wiley Date: To: exim users Subject: Re: [exim] Rules for HELO
Marc Perkel wrote: > What are the rules for HELO?
One thing that bit us a couple of years
ago was checking for strict domain
format compliance. Some Exchange boxes
will include a "_" in their HELO's. I
think it's because Exchange uses the
Windows computer name in a HELO. Under-
scores are perfectly legal characters for
Windows host names but not for DNS
domains. So we add:
