Hi, I have exchange 2007 environment with following roles. 1- CCRs for mailbox with different two AD sites. Seperate CCR for both sites 2- CAS/HUB servers (both roles in a server) with different two AD sites. 2 HUb/CAS in each site 3- 2 edge servers with different two AD sites. 2 Edge in each site. Now problem is that 1hub server in AD site B in not able to receive emails from HUB server located in AD site A and not able to receive emails from edge servers as well located in site B itself. Intresting fact is that another hub server in AD site B is receiving emails from HUB server located in site A and also able to receive emails from edge server. Any suggestions would be highly appreciated.

Please try to drop an email using Telnet and see what happens Please check and make sure the Microsoft Exchange Transport service is started using Network service account. It should not be with the local system account Exchange Rocks

More Infomation required. What exactly happens when the messages arent received by that hub transport? Error messages in logs? NDRs etc... Also, run ExBpa against the servers.

Can you look at the Event log on the hub server that does not receive e-mail?

Hi Gautam, can you check below thing ! 1: Check whether you have created any receive connector on HUB1 in site B where you have given scope of entire subnet of exchange. If yes then please cope it only for required host. 2: have you added this HUB server recently and what about EDGE sync for both HUB. 3: Send message from EDGE to HUB1 thru SMTP command and see what error message you are getting. Anil

HT servers in the same organizations start a smpt session with each other directly and do not go through EDGE. having said that. on the HT server in the site B please watch that server peformance issues. also look at the get-queue -identity <queueid> |fl and look at the last retry error. that is wher you start with in troubleshooting what is think it is and i have seen in past is performance issues(perhaps backpreasure) with the server that is not recieving emails.Dhruv

Guys, Here are the answers of your queries. 1)- Email is getting received using telnet session. 2)- MS transport service is started using network service account. 3)- There is no NDR. Only error message is remote queue is – 451 4.4.0 Primary target IP address responded with; “421 4.4.2 connection dropped.” Attempted failover to alternate host, but that did not succeed. Either there are no alternate hosts, or delivery failed to all alternate hosts. 4)- There is no error in Exbpa. 5)- Nothing found in event logs, specific related to this problem. 6)- Another receive connector is there but that is only for receiving application emails and required host entries are there instead of entire subnet. 7)- This is an old HUB server which was getting emails previously and edge sync is working fine and this server is able to send emails. Problem is in email receiving only. 8)- I will check and let you know the result after sending email through SMTP command from edge to hub. However, please send me the specific steps to send emails using SMTP command. 9)- server performance is fine for this server and if it is due to back pressure then there must be events generated for this but there is no event in event logs.

Can you take one reboot of HUB server to check it !, Please find below for sending test mail thru SMTP Command How To Test SMTP Services Manually in Windows Server 2003:: http://support.microsoft.com/kb/323350 Anil

Gautam, yes i would also recomend reboot. as this has worked for me in past. for one of my clients i had the same error in the queue. as i said earlier this is due to performance issue on the recieving HTDhruv

I have already rebooted the server many times with no success. The SMTP connection is perfect. I received the email through this procedure (SMTP command).

Hi, Is there any error message in Application log on Edge Server? To troubleshoot the issue, I suggest you renew Edge subscription and the Edge Server and the problematic Hub Server for a test. 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.

There is no error on edge server specific to this problem and edge subscription has already been tried but the situation is same.

Hello Gautam, Did you ever get this resolved? Based on the message you pasted above from the queue, it points to an authentication issue potentially between the servers. This could explain why telnet works (as you are sending from a user account and not a machine account). Can you check the following on the affect hub/transport servers: 1. Open the Exchange Management Console 2. Under server configuration, click to highlight the Hub Transport Container 3. On the right hand pane, highlight the affected server. At the bottom, highlight the Default Receive Connector (usually looks like "Default servername"), then go to the properties 4. Click the authentication tab, then ensure that "Exchange Server Authentication" is enabled 5. Switch to the "Permission Groups" tab, then ensure that "Exchange Servers" is enabled 6. If these look correct, compare these same 2 permissions between all hub/transport servers If this doesn't lead you anywhere, you may consider enabling protocol logging on the affected servers to see if we can get some more detailed information on the traffic being passed between them: http://technet.microsoft.com/en-us/library/aa997624.aspx Hope this helps! Kevin Ca - MSFT Kevin Ca - MSFT