[KLUG Members] Issues send/receiving email to one domain

[Adam Williams]

> I have box that I can not send or recieve emails from one particular company 
> (domain).  Obviously both sides are having the same problem and both have no 
> problems sending or receiving emails from anywhere else.
> Here is a snip from the sendmail log:
> Jun  1 04:06:05 linuxserver sendmail[2996]: h4V0mVrg001458: 
> to=<user@domain.com>, ctladdr=<admin@name.domain.com> (5 00/500), 
> delay=1+07:17:34, xdelay=00:00:12, mailer=esmtp, pri=3000364, 
> relay=mailserver.domain1.com. [12.34.56.78],  dsn=4.0.0, stat=Deferred: 421 
> SMTP service not available, closing transmission channel
> Is there any way to find out which end could causing the problems.  I did 
> telnet in to the othe mailserver on port 25 and type HELO and I get a "421 SMTP 
> service not available, closing transmission channel"  But i am not usre if that 
> is a good test as if there mail server is set-up correctly to dissallow 
> relaying wouldn't I get theis error?

Any chance you have some SPAM filtering enabled on these boxes?