We have a Windows Server 2003 DC with Exchange Server installed. Everything was working fine, e-mail was being received and sent. There was a power surge overnight which shut off all the workstations: one workstation had to be manually reconnected to the domain because the "Trust Relationship" between it and the domain was broken. The others restarted/reconnected fine. The big problem is that now we can't receive e-mails. The sender gets an Undeliverable message indicating a "communications error". We CAN forward e-mails INTERNALLY and we CAN send e-mails. We just can't receive them. I realize I haven't given you much hard information but I'm not quite sure what is needed. Any ideas or pointers to resolve this would be most appreciated.

On Wed, 2 Feb 2011 21:32:47 +0000, nlk11021 wrote: > > >We have a Windows Server 2003 DC with Exchange Server installed. Everything was working fine, e-mail was being received and sent. > >There was a power surge overnight which shut off all the workstations: one workstation had to be manually reconnected to the domain because the "Trust Relationship" between it and the domain was broken. The others restarted/reconnected fine. > >The big problem is that now we can't receive e-mails. The sender gets an Undeliverable message indicating a "communications error". We CAN forward e-mails INTERNALLY and we CAN send e-mails. We just can't receive them. > >I realize I haven't given you much hard information but I'm not quite sure what is needed. Any ideas or pointers to resolve this would be most appreciated. From the Exchange server, can you "telnet 127.0.0.1 25"? From another machine on your LAN, can you "telnet <servername> 25"? If you can then the problem is probably at your firewall. --- Rich Matheisen MCSE+I, Exchange MVP --- Rich Matheisen MCSE+I, Exchange MVP

Hi, Does the issue only occur when trying to get the message from external E-Mail address? First, please use the Telnet command and verify whether the message can be sent from another side to the problematic server as Rich mentioned. To run the command, please refer to the following article: http://support.microsoft.com/kb/153119 This issue usually can occur by firewall, recipient policy settings or authentication. If the issue persists, please post the detail NDR here for research. Thanks. NovakPlease 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.