Hi Daniel,

> > Please make sure it works by sending an email from gmail (which allows an
> > empty "To:" field and many "Bcc:" - yahoo and hotmail don't allow it) and send
> > to multiple recipients in the Bcc with one of those recipients as your mail
> > server with the stock sendmail.mc and sendmail.cf, this would then be an
> > identical test to what I'm doing.
> 
> I just tried (again) from mutt, which allows empty To: and Cc: 
> lines.  This time I Bcc:'ed you as well.  Let me know if you get it 
> (subject: test2).  I got this and my previous test just fine on my 
> stock sendmail server (well, stock minus "allow unresolved 
> hostnames" which I always comment out).

Many thanks for your help here mate. After quite some more trouble-shooting I
have found the issue.

I use the smf-zombie milter to block many of the botnets around, however this
milter has the disadvantage that it also blocks those types of emails.
Searching it's source shows the "To and CC field not filled in" error.

I tried to find a way I could just stop the milter from rejecting the
"undisclosed recipient" emails, but I could not without recoding it myself, so
basically I just removed the milter (and noticed an increase in spam entering
the environment since doing it).

I have emailed the author and joined their smfs-users mailing list, and sent
an email yesterday asking about the best way forward to being able to use the
milter while disabling the "undisclosed recipients" check. Haven't received
any replies yet.

So lastly, I have received your test email so thankyou, the milter is disabled
so isn't rejecting those emails anymore.

Regards,

Michael.

> Dan W.
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