I can't email other users within my AD environment. We are all in the same domain however they host their Exchange 2010 and the mx record points back to my domain where Exchange lives and now we cannot email each other. However some people can mail to me just fine. If I try to email from myself@mycompany to enduser@theircompany.com and vice versa and it does not come thru even though we are all in the same domain. We can both email everywhere else just fine but when it comes to mailing to others in my doman I get nothing.

Trace the MX record and associated A records in DNS starting at the Exchange server.Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."

What about the configuration of the send connectors. Are there sepcial connectors configured for the mailing between your domains? regards Thomas Paetzold visit my blog on: http://sus42.wordpress.com

Hi, At first ,make sure MX records are configured correctly at both side. You’d better add a host A record at each side. You could use Nslookup to Verify MX record configuration at both side. How to use Nslookup http://technet.microsoft.com/en-au/library/aa998082(EXCHG.65).aspx Do a ping test make sure the connection is ok. Check the send connector at each side. 1. Make sure all the FQDN not filled with IP address. 2.Add each other’s address Space into the Address Space list. For how to configure send connector http://technet.microsoft.com/en-au/library/aa998662.aspxPlease 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.