I'm a n00b, I'll admit, but I'm having trouble with my sendmail now, and it was working fine a couple weeks ago.
I really don't know what to make of this error so I was wondering if you could translate it for me and help me out if possible, thanks
Which version of Sendmail do you have? They keep changing the way addresses without PTR entries are handled and its often confusing whether its turned off or on. Also, try the sendmail website. Like most opensource projects they have very in-depth support.