501 5.1.8 Bad address syntax

Hi All,

I am admin to a mixed Exchange 2007/2003 organization. Using an Edge server but also a FrontEnd Exchange 2003 server.
To one particular domain i am having trouble to telnet to their mailserver. As soon as i enter mail from: address@mydomain.com I get the response 501 5.1.8. Bad adress syntax.

It only happens to this domain. All others are working fine.
What am i missing? is tehir config no good, or do i need to change something?

thanks in advance

gerardtimmersAsked:
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

x
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Neil RussellTechnical Development LeadCommented:
If it is happening when you telnet to THEIR mail server then the issue is not you or your systems, it is theirs.
0
Neil RussellTechnical Development LeadCommented:
What happens if you try a mail from user@yahoo.com ? Same result?
0
gerardtimmersAuthor Commented:
Hi Neilsr,

Yes i am telnetting to their mail server. Can you please elaborate a bit more why you are convinced the error is on their side?
Wouldn't they have more issues with receiving mail from other domains than ours?

thanks
0
Creating Active Directory Users from a Text File

If your organization has a need to mass-create AD user accounts, watch this video to see how its done without the need for scripting or other unnecessary complexities.

gerardtimmersAuthor Commented:
yep indeed i got the same result:
220 theirmailserver ESMTP CB
ehlo yahoo.com
250-theirmailservername
250-8BITMIME
250-ENHANCEDSTATUSCODES
250-DSN
250 SIZE 26214400
mail from:gerardt@yahoo.com
501 5.1.8 Bad address syntax

but I think this happens here because i am causing a rDNS error. As the Yahoo.com servers' rDNS is completely different as the address i am telnetting from.
0
Hendrik WieseInformation Security ManagerCommented:
0
gerardtimmersAuthor Commented:
Hi Hendrik,
Thanks, but i have read this link and also the embedded one already. But I get the error already during the initialization of the smtp session. Directly after the mail from: command.
Also this happens on a DMZ located Exchange 2007 Edge server, an Exchange 2007 hub/transport server in the LAN and a EXchange 2003 FrontEnd server. And they are all NATting to a different public IP address.
And it only happens to one domain. Tried several other domains from our customers/partners, they all go fine except this one.

i am puzzled...

0
Hendrik WieseInformation Security ManagerCommented:
What happens when you telnet to your server in question from one of your customers machines?
0
gerardtimmersAuthor Commented:
sorry, that's on their LAN  and i do not have access to it.
0
Hendrik WieseInformation Security ManagerCommented:
Have a look at the following, and let me know if it helps?

http://classicasp.aspfaq.com/email/why-is-e-mail-to-certain-domains-being-rejected.html
0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Exchange

From novice to tech pro — start learning today.