OK. so it's not a DNS problem. Then what the heck would cause this error? The SBS server can send receive emails. I just get these 550 errors on certain clients. I've been trying to pinpoint if it was with a specific few domains or not.
Troy > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] Behalf Of R. > Scott Perry > Sent: Tuesday, November 25, 2003 12:11 PM > To: [EMAIL PROTECTED] > Subject: Re: [IMail Forum] OT: 550 Invalid domain: smells like bad DNS > > > > >Need some direction here. I've got a domain called > sofmail.com that we use > >for our Small Business Server 2003. I've got a user who gets > a "550 Invalid > >domain sofmail.com" error when sending to several external accounts. > > The message implies that sofmail.com either isn't a real > domain, or can't > accept E-mail. However, > http://www.dnsstuff.com/tools/traversal.ch?name=sofmail.com&ty > pe=MX shows > that no matter which DNS servers are used, the domain does > indeed exist and > has an MX record. There doesn't seem to be any justification > for the error > message you received. > > >My concern is that the DNS host (MCI) didn't setup the > reverse DNS correctly. > > That shouldn't be the problem -- if there was a problem with > the reverse > DNS entry, you should be seeing a different error message > (such as "550 IP > 192.0.2.25 doesn't resolve"), that refers to the IP rather > than the domain. > > >Being that I'm not a DNS guru I was hoping perhaps someone > could shed some > >light on what's pointing where. I'm thinking that the > recipient's mail > >server is doing a reverse lookup for sofmail.com and can't > find it. I think > >MCI created a PTR for mail.sofmail.com. What should it be? > > For reverse DNS (which I don't think is the problem here), > the IP address > that the outgoing mail is sent from is the one that needs to > have a reverse > DNS entry. If the E-mail is sent from an IP 192.0.2.25, then > 192.0.2.25 is > the one that needs the reverse DNS entry (even if there are > other IPs that > the mailserver uses). http://www.DNSstuff.com has a Reverse > DNS Lookup > tool that helps point out reverse DNS problems. > > -Scott > --- > Declude JunkMail: The advanced anti-spam solution for IMail > mailservers. > Declude Virus: Catches known viruses and is the leader in mailserver > vulnerability detection. > Find out what you've been missing: Ask about our free 30-day > evaluation. > > --- > [This E-mail was scanned for viruses by Declude Virus (http://www.declude.com)] To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/ To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/
