Email mot sending to certain domains

[pghnetguy]

I just upgraded to SBS2008/Excange 2007 from SBS2000. Since the migration, email to certain domains (comcast.net, verizon.net, gmail) is not going through.

Our users do not ever get an NDR indicating the message was not delivered. The outbound SMTP logs seem to indicate that he message successfully leaves our server.

We have a fixed IP, and the ISP has a reverse DNS entry to verify the domain.

This all worked fine before the the migration but I can't see anything on the new server that would be causing the problem.

Any insights would be appreciated.

Thanks

 

[Zelandakh]

Do a telnet session to one of them on port 25 and have a chat with their servers. You'll probably find that they are rejecting your message for some reason. Once you find out why, we can tackle resolving it.

Unless they are claiming you are a spammer in which case you won't get any joy - I've been trying for 4 months to get Earthlink to stop listing me as a spammer and they won't even acknowledge my job ticket...

 

[xmsre]

A blacklist somewhere is a good guess, but Zelandakh is right; It's better to test the connection by telnet to port 25 and find out what error you get. I prefer working with facts any day. Now, as for Zelandakh, how do I know you're not a spammer? ;-)

 

[58sniper]

People on the other side of the pond go to the bottom of the job queue....

Pat Richard MVP
Plan for performance, and capacity takes care of itself. Plan for capacity, and suffer poor performance.

http://www.ucblogs.net/blogs/exchange/

 

[Zelandakh]

Me no spammer. I'm an entirely legitimate user with a static IP.

Honest Guv.

And I got to the top of the job queue and now have a paying job once again.

 

[pghnetguy]

Thanks all. For some strange reason this suddenly started working to the domain in question.

 

[Zelandakh]

Blacklist - they took you off.