Recently I installed Exchange 2010 and its working just fine. I can send mail to and from Exchange 2010 to any outside domain (Gmail and Yahoo, for example). I have an older Mail server on the domain as well, which does most of the mail handling right now. And that mail server has Exchange2010 listed as a peer server. When I try to send from the Exchange mail server to the other mail server, it bounces back and provides the following error Message: Diagnostic Information for administrators: Generating server: Exchange.domain.ca m.schroeder@domain.ca #554 5.4.4. SMTPSEND.DNS.Mxloopback;DNS records for this domain are configured in a loop ##

The server is probably doing a lookup on the MX records which come back to you. If the other server is on the same network, the easiest way is to create a second Send Connector. Set it to use a smart host and enter the IP address of the other server. On the Address Space tab enter the domain/s that server is responsible for. Exchange will not do any DNS lookup for that domain, just send it straight to that server. Simon.Simon Butler, Exchange MVP Blog | Exchange Resources | In the UK? Hire Me.

Hello I agree with Simon suggestion you can also add receive connector add the ip for other exchange for relaying emails. Thanks Mhussain

I believe I had tried that. I just went through and removed all of Exchange, and going to spend all of today on it. Hopefully I can get it working.

better you remove send connectors again and recreate them. when you create it as the type make sure you choose "internet"Dishan M. Francis www.rebeladmin.com

Hi, How about the issue? Simon’s suggestion is right. Do you follow his suggestion to configure on your Exchange Server? Here are some related documents for you: Create an SMTP Send Connector http://technet.microsoft.com/en-us/library/aa997285.aspx Configure Send Connector Properties http://technet.microsoft.com/en-us/library/bb629503.aspx Best Regards, EvanPlease remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

Hello Dishan, In the Send Connectors->Address Space. I added SMTP *.domain.ca,*,internet provider their mail server, and domain.ca. Also under the Send Connector->Network I changed the setting to route mail through the following smart hosts: mail.domain.ca(registered with a DNS provider) and mail2.visions.ca(registered with a DNS provider) and the ip address of the other mail server. Now its working!! Yay. Thank you guys for all the help.