We have a user who left the organization about a year ago. This users domain email account has been deleted for well over 9 months. When we try to send an e-mail to his personnal external e-mail account we get the following NDR telling us we were sending to his old Domain e-mail account Your message did not reach some or all of the intended recipients. Subject: Test from XXXXXXXXXXXXXXXXXXXX Sent: 7/27/2012 9:14 AM The following recipient(s) cannot be reached: User.Name@ourorg.com on 7/27/2012 9:14 AM The e-mail account does not exist at the organization this message was sent to. Check the e-mail address, or contact the recipient directly to find out the correct address. <mail.ourorg.com #5.1.1> We are running exchange 2003 SP2 with all updates. I have searched all of AD and this email address in not present anywhere. There are no contacts for him anywhere. Any clues to why this is happening would be greatly appreciated. Russ

Are you sure there isn't a personal contact in your outlook? Maybe nickname cache? When you start typing the external address and starts to auto complete click the delete button, then try sending again. Does his external email address also use the same convention user.name@externaladdress.com? James Chong MCITP | EA | EMA; MCSE | M+, S+ Security+, Project+, ITIL msexchangetips.blogspot.com

This issue affects all users trying to send to this external address. We have tested with several different users who have never sent to this address before and no luck. We have even gone as far as creating new test accounts and sent the email from the new accounts with the same results. The 2 users who originally had (and still have) the issue we did clear their auto correct entries. I am fairly sure it is in Exchange or AD somewhere but I can't find it. his external email address does not use the user.name@ format it is in the xxxxxxx@x.xxx format Russ

1. Do an ldifde dump of AD then open notepad do a search for both the internal and external address. ldifde -f export.ldf -s MYDC 2. Maybe someone registered a hidden event sink. http://msexchangetips.blogspot.com/2006/08/exchange-how-to-view-all-registered.htmlJames Chong MCITP | EA | EMA; MCSE | M+, S+ Security+, Project+, ITIL msexchangetips.blogspot.com

I did an export on all domains and neither address was found in the searches. I searched for all and even part of the addresses with no luck.Russ

Just as a test can you create an exchange contact and set to this external address than send to the contact and see if it goes out. If it still fails than possible there is a sink in exchange doing the forwarding. Also are you able to send to another user in that domain? James Chong MCITP | EA | EMA; MCSE | M+, S+ Security+, Project+, ITIL msexchangetips.blogspot.com

I created the contact and set the external address and still get the same result. An NDR from his old internal address. We do not have another address in that domain we can send to Russ

Hello Russ, If it still not work when you input the external account email address, this may there is rule or forward setting on external account that route emails to User.Name@ourorg.com? You can use one external account, send one email to that users external account: If you still get the NDR, this may he have sat forward or rule on his external account (that route email to user.Name@ourorg.com). If the external account not receive the NDR information, please go to check whether there is one transport rule redirect the emails to user.Name@ourorg.com on your Exchange Server. Thanks, Evan Liu TechNet Subscriber Support in forum If you have any feedback on our support, please contact tngfb@microsoft.com Evan Liu TechNet Community Support

Hello Russ, If it still not work when you input the external account email address, this may there is rule or forward setting on external account that route emails to User.Name@ourorg.com? You can use one external account, send one email to that users external account: If you still get the NDR, this may he have sat forward or rule on his external account (that route email to user.Name@ourorg.com). If the external account not receive the NDR information, please go to check whether there is one transport rule redirect the emails to user.Name@ourorg.com on your Exchange Server. Thanks, Evan Liu TechNet Subscriber Support in forum If you have any feedback on our support, please contact tngfb@microsoft.com Evan Liu TechNet Community Support

From an external account ie. hotmail you can send to this external addresss? Please go through my blog to check for any registered event sinks that may be doing the forwarding. 2. Maybe someone registered a hidden event sink. http://msexchangetips.blogspot.com/2006/08/exchange-how-to-view-all-registered.html James Chong MCITP | EA | EMA; MCSE | M+, S+ Security+, Project+, ITIL msexchangetips.blogspot.com

From an external account ie. hotmail you can send to this external addresss? Please go through my blog to check for any registered event sinks that may be doing the forwarding. 2. Maybe someone registered a hidden event sink. http://msexchangetips.blogspot.com/2006/08/exchange-how-to-view-all-registered.html James Chong MCITP | EA | EMA; MCSE | M+, S+ Security+, Project+, ITIL msexchangetips.blogspot.com

I checked all the event sync's in the export and there not any. We did find out we can't send to this address from an external address either. However, this does not explain why we gat an NDR as if it was sent to an old Domain account and not an external account.Russ

what if you do a custom ldap search in AD proxyaddresses=smtp:emai@yourorg.com Does it return anything?Sukh

It does not return anything. I searched for both the Internal and external addresses just to be sure. I test the query with a good, known address just to be sure.Russ

Can you up the logging for SMTP& in particular the categoriser and see what the app log saysSukh

I checked all the event sync's in the export and there not any. We did find out we can't send to this address from an external address either. However, this does not explain why we gat an NDR as if it was sent to an old Domain account and not an external account. Russ Hello Russ, Just as I said before, this may he has sat his external account forward the emails to User.Name@ourorg.com. When you send email to his external account, it will redirect the emails to User.Name@ourorg.com, but the account (User.Name@ourorg.com)has been removed from your organization, so you get NDR for email to User.Name@ourorg.com. You can ask he go to check whether he has sat forward on his external account. Thanks, Evan Liu TechNet Subscriber Support in forum If you have any feedback on our support, please contacttngfb@microsoft.com Evan Liu TechNet Community Support

How about the issue, any updates? Thanks, Evan Liu TechNet Subscriber Support in forum If you have any feedback on our support, please contacttngfb@microsoft.com Evan Liu TechNet Community Support

I have not had a chance to work this issue since my last post. I am hoping to be able to increase the logging today. As I indicated before, we are even unable to send to this external address from another account. My concern is, we are only seeing this with 1 address at present but could potentially have more issues.Russ

If you cant send to this external account from another external then the issue is outside of exch and your env.Sukh

Ok. I got logging increased and I was also able to get with our Network guys to packet capture in and out and indeed the external address is set to forward back to our organization as you suggested earlier. I also enabled recipient filtering (which wasn't turned on) and the internal NDR's disappeared. I thank everyone for all their help and also teaching me a few things I did not know. :) Russ

Glad the issue has been found now. Thanks, Evan Liu TechNet Subscriber Support in forum If you have any feedback on our support, please contacttngfb@microsoft.comEvan Liu TechNet Community Support