Need your opinion on Exhange problem

[mrbios]

Hi Everyone,

Right now we're having troubles sending out emails with an Exchange 2003 server. What seems to be the BIG problem to me is that we repeatedly get marked as spam. I did a little looking into this, and I believe I've found the problem.

I looked at the headers of one of the few emails that got through to one of my personal email accounts, and our email server's IP ends in .16, but in the headers it's showing up as .6 instead. www.spamhaus.org has the .6 IP flagged because of this. I'm not the guy who looks after our DNS, but he checked into it (and I did an ANY/ALL DNS lookup from dnsstuff.com), and there's nothing that's pointing the .6 IP address. This leads me to believe that there are two possible problems:

-Exchange isn't configured correctly
-Some kind of possible firewall problem?

As I was not the one who set up our firewall, nor the one who installed Exchange, it's hard for me to pinpoint the problem. If you could provide any assistance, that would be awesome.

BTW, I did just try sending some emails to my email server, and it seems like they're not getting through now. Trying to go to the wrong IP address (.6) perhaps?

If it would be of any assistance, I could also post one of the headers of the emails that have gotten through.

As a side note, when I did a test on www.dnsreport.com, it came to my attention that there wasn't a reverse DNS record. This has been added now, but that takes time to update, so maybe that might fix my problem as well.

 

[InlineFour]

Turn off your spam filter on one of your personal email addresses and see if the email goes through. If it does, then it means you're being reported as a spammer.

You'll need to configure a reverse DNS record with your ISP (already done). Give it 24 hours for the settings to take effect. You should also have a static IP address.

 

[alent1234]

if the A records are wrong in DNS just fix them

 

[RebateMonger]

Check incoming status of Exchange:

1) Look up your first MX record in DNSReport.com (i.e. smtp.mydomain.com)
2) Telnet to that location, using TCP Port 25 (i.e. "Telnet smtp.mydomain.com 25")
3) If the Exchange Server answers, then your incoming mail is fine and you don't have firewall problems.
(Note: Be sure to Telnet from OUTSIDE your network, and be sure that there's nothing blocking outbound Port 25 from that outside site)

Check outgoing status of Exchange:
If you don't meet the following requirements, you may be flagged as SPAM by some mailservers:

a) Have a static IP address?
b) Have a RDNS listing for your mailserver's IP address?
c) Your Exchange Server's name corresponds to the DNS name of your IP address?
(i.e. If the FQDN of your Exchange Server (as shown in Exchange) is "smtp.mydomain.com", then you need to have a public DNS record that includes "smtp.mydomain.com" at the SAME IP ADDRESS as your Exchange Server)

Most don't enforce that last condition, but AOL, for instance, will eventually decide you are probably a spammer if your email server's name doesn't match one of your public DNS host records/IP address combinations.

How could you have a "guy who looks after our DNS" and not have a Reverse DNS Record? Jeepers!
Do you have an SPF record?

 

[mrbios]

Hey everybody,

Thanks for the help so far. Sending out emails is now working perfectly, now that the reverse record is in place. However, receiving email doesn't work at all. Sending within the same domain (meaning it's never leaving the server) works fine, but trying to send email to this server never works at all. Any suggestions?

 

[tfinch2]

Originally posted by: mrbios
Hey everybody,

Thanks for the help so far. Sending out emails is now working perfectly, now that the reverse record is in place. However, receiving email doesn't work at all. Sending within the same domain (meaning it's never leaving the server) works fine, but trying to send email to this server never works at all. Any suggestions?

Is everything okay with your MX record on your external DNS?

 

[RebateMonger]

So, can you Telnet into your Exchange Server or not?

If you reach the Exchange Server with "Telnet xxx.xxx.xxx.xxx 25", but not with "Telnet mydomain.com 25", then you have a Public DNS problem.

If you can't reach the Exchange Server with EITHER method, then you have a firewall, routing, or port forwarding problem, or else your Exchange Server isn't listening on your external NIC.

 

[mrbios]

Hi,

Sorry, I should've mentioned it earlier. I can telnet in both through the internal IP, external IP, and the DNS name.

 

[RebateMonger]

What does your Exchange Server's Queue look like? Are there incoming messages waiting for something?

 

[mrbios]

Originally posted by: RebateMonger
What does your Exchange Server's Queue look like? Are there incoming messages waiting for something?

There are no messages in the queues. Most email I try send to this server never arrives, and about 4 hours later I get an undeliverable mail message back. What's odd is that the last email I tried to send bounced back in about a minute.

 

[mrbios]

I think I've found my problem. One of my email accounts actually gave something of use to the problem in the undeliverable message:

Failed to deliver to 'testtest@blahblahblah.com'
SMTP module(domain blahblahblah.com) reports:
return-path address <mrbios@somethingsomething.net> rejected by mail.blahblahblah.com:
530 5.7.3 Client was not authenticated

Real server names removed.

The previous rejection message was:

mail.echeetahsoft.com: no response