Unable to recieve external emails

I have disabled the Symantec Antispam for Exchange to see if that helps.

DNS Lookup gives me the following error saying it can't find my mail servers:

ERROR: I could not complete a connection to any of your mailservers!

smtp-04.marketresourcepartners.com: Timed out [Last data sent: MAIL FROM: ]
smtp-03.marketresourcepartners.com: Timed out [Last data sent: MAIL FROM: ]
smtp-02.marketresourcepartners.com: Timed out [Last data sent: MAIL FROM: ]

If this is a timeout problem, note that the DNSreport only waits about 40 seconds for responses, so your mail *may* work fine in this case but you will need to use testing tools specifically designed for such situations to be certain.

Can you telnet to port 25 using the external ip of the mail server?

No telnet is not working

It gives me the folllwing: 220 *****0*********************************************
0****0****0 *********************200***2********0*00

Ping and nslookup give me the correct credentials from an external source to my smtp and email server

I had to restart my exchange server and everything is back to normal we are able to send and recieve emails. But I am still getting this warning in DNS lookup, can someone help me understand this better:

WARNING: One or more of your mailservers is claiming to be a host other than what it really is (the SMTP greeting should be a 3-digit code, followed by a space or a dash, then the host name). If your mailserver sends out E-mail using this domain in its EHLO or HELO, your E-mail might get blocked by anti-spam software. This is also a technical violation of RFC821 4.3 (and RFC2821 4.3.1). Note that the hostname given in the SMTP greeting should have an A record pointing back to the same server. Note that this one test may use a cached DNS record.

smtp-02.marketresourcepartners.com claims to be invalid hostname '*****02*********************************************************************0****0****0': <br />   220 *****02*********************************************************************0****0****0 *********************200************0*00 <br />smtp-04.marketresourcepartners.com claims to be invalid hostname '*****0**********************************************************************0****0****0': <br />   220 *****0**********************************************************************0****0****0 *********************200************0*00 <br />smtp-03.marketresourcepartners.com claims to be invalid hostname '*****0**********************************************************************0****0****0': <br />   220 *****0**********************************************************************0****0****0 *********************200************0*00 <br />

Hi Simon,

Thanks for the reply. Have applied that change to the PIX. THe SMTP service is running and no permissions have been changed. What I have noticed though is that in the application log on the Exchange server:

vent Type:      Error
Event Source:      MSExchangeTransport
Event Category:      SMTP Protocol
Event ID:      7010
Date:            10/8/2007
Time:            7:53:28 PM
User:            N/A
Computer:      EXCHANGE
Description:
This is an SMTP protocol log for virtual server ID 3, connection #83. The client at "76.103.161.212" sent a "helo" command, and the SMTP server responded with "501 5.5.4 Invalid Address  ". The full command sent was "helo pre-nrcw396w1e7.hsd1.ca.comcast.net.".  This will probably cause the connection to fail.

The connection # for the virtual server keeps on incrementing and it had reached something like 10000 before we stopped recieving emails. Is there some DNS check I should do? THanks.

Have you restarted the SMTP Server Service?
If not then I would suggest that you do that to begin with.
A number of connections in the SMTP configuration is not good. The PIX configuration may have caused that.

Simon.

--
If your question has been answered, pleased remember to accept the answer and close the question.

Hi Simon,

I restarted the SMTP server but the errors mentioned above are still present. Thanks,

Abhi

The last error that you posted was a sending error, not a receiving error. That does not indicate why you cannot receive email, if that is indeed still the case.

Simon.

--
If your question has been answered, pleased remember to accept the answer and close the question.

Oh Ok, I was under the impression that was a recieving error logged by our Exchange.  We have started recieving external emails. How should I troubleshoot the above error? Thanks.

That error doesn't really say enough. Do you know that your DNS is configured correclty? Put your domain in to dnsreport.com and see if it flags any errors in the mail server section.

Simon.

--
If your question has been answered, pleased remember to accept the answer and close the question.