Exchange Server Forums

Email Bounce back with SMTP error 550&571

Users viewing this topic: none

Logged in as: Guest

Printable Version

All Forums >> [Microsoft Exchange 2003] >> Message Routing >> Email Bounce back with SMTP error 550&571

Page: [1]

Message

<< Older Topic Newer Topic >>

Email Bounce back with SMTP error 550&571 - 2.Jul.2008 6:46:39 AM

gerald1224

Posts: 3
Joined: 19.Feb.2007
Status: offline

Hello everyone can you please help me to solve our email problem.

I’m not that experienced on Exchange Server. Our mail server is Exchange 2003. The problem that I’m facing is some companies cannot send emails to us they said the email they send to us bounce back to them, and also vice versa some of my user try to send email to outside they received bounced email too. Usually the SMTP error are 550 & 571 which unknown user or cannot verified user. To see more clearly with my scenario here is our mail setup:

We have 2 domain

Domain A has mx record with our ISP, and configure to our mail server which mail.domanA.com
Domain B which is hosted to another Web Hosting Company. Which is DomainB.com (have their own MX record)

Previously we are using our email as user@domainA.com, but the
company management want to change it to user@DomainB.com to make as the primary email address for the company. So what I did is I created a recipients policy on the exchange server to have @DomainB.com as the primary email address. Also as advice from our ISP where our mx record is, they told me that DomainB(HOSTCOMPANY) need to configure the DNS for the mx record for DomainB to forward it to the mx record of our Domain which DomainA. Now DomainB has now forwarded the mx record to DomainA. Its works, but not perfectly.
Now we are receiving calls from other companies telling us that they cannot send email to us and also vice versa some of our user said that cannot send email to other companies also. But on our old email account which @DomainA.com works fine. How can i availble to fix this problem and what else should i do to, is there any setting should i do our our mail server to be able to send and receive email from our new email account?

Please I really need your help

Thanks

Gerald

Post #: 1

Featured Links*

RE: Email Bounce back with SMTP error 550&571 - 2.Jul.2008 9:22:50 AM

Sembee

Posts: 2716
Joined: 17.Jan.2008
From: Somewhere near London, UK
Status: offline

What a mess.
Check the MX records for the domain that you want to use and ensure that they are ALL pointing to the Exchange server. It is not unheard of for hosts to leave their own servers in place.
If you know who is sending you email and getting rejects then ask them if they use the same host that you do. Most ISPs systems are setup to presume that they are responsible for everything connected to a domain and cannot cope with a setup where another server deals with email.

The verification failure might be down to non-matching reverse DNS records. Have you confirmed that reverse DNS etc is configured correctly?

Simon.

_____________________________

Simon Butler,
Exchange MVP
Blog: http://www.sembee.co.uk/
Web: http://www.amset.info/
In the UK? Hire me: http://www.amset.co.uk/

(in reply to gerald1224)

Post #: 2

RE: Email Bounce back with SMTP error 550&571 - 2.Jul.2008 12:05:10 PM

gerald1224

Posts: 3
Joined: 19.Feb.2007
Status: offline

Hi Mr. Sembee.
Thanks for the reply.
Yeah I know Im in totally mess right now for my mail server, it gives me headache.
Regarding on reverse DNS it is configures properly, I 'm just not sure if we configured properly the forwarding of the MX record to our domain(DomainA).
We just updated the DNS setting , what we did is we created a custom DNS A record on DomainB with DATA of the MX record of DomainA and we created a custom MX record for DomainB(mail.DomainB.com) with DATA of
MX Record of DomainA.. Its looks like this:
Ex.
DomainA MX record: 68.175.68.71
DNS A record mail.DomainB.com 68.175.68.71
MX mail.DomainB.com 1 68.175.86.171

I dont know if this correct. will see after 24 to 48 hrs.

Thanks

Gerald

(in reply to Sembee)

Post #: 3