Hi There, We found the following behaviour regarding email addresses and mailrouting between Exchange 2003 and Exchange 2007.We have address policies in place, but for some users we customize the primary email address. So after an Exchange 2007 user is created the email address policy is stamped on the object and the 'proxyaddresses' and 'mail' attributes are set. After this we set the EmailAddressPoliciesEnabled to $false and add and change the primary email address and remove the original one using the Exchange management console. This changes the primary proxyaddress (SMTP:....) but does NOT change the mail attribute (windowsemailaddress). When we now send email to this Exchange 2007 user from 2003 the mail gets routed to the Exchange 2003 server hosting the Routing Group connector to Exchange 2007 and gets bounced by 2007 because Exchange 2003 uses the mail attribute in the "Envelope to:"(and MIME to: header also). Exchange 2007 does not use the mail attribute in its lookups it seems and generates an NDR.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.<servername #5.1.1> Has any of you seen this described in any of the published documentation? Is this a documented change or maybe a bug in the Console. (Bug in the sense of that it should also change the mail attribute)? using E2K3 SP2 & E2K7 + rollup 4 Regards, Mark

Ok the issue seems to be a bit different than we thought. It is not only Exchange 2007 that is bouncing the email, but both messaging systems. We have a user with the following AD attrbutes: >proxyAddresses: SMTP:user.van.der.test3@domain.com;>mail: test.uservan2@domain.com When I send an email to this userusing Outlook 2003 connected to an Exchange 2003 server the TO: address wil be test.uservan2@domain.com, which generates a NDR because this address does not exist as an valid email address When I send an email to this user using Outlook 2003 connected to an Exchange 2007 server the TO: address will be user.van.der.test3@domain.com , which will be delivered to the mailbox. Why is this happening??? We have a couple of users with mismatching mail and proxyAddresses fields because when changing the primary proxy address using the Exchange Management Console, the mail attribute is not changed. Cheers, Mark

Your proxyAddresses primary smtp address "SMTP:<user>@domain.com" should match the mail attribute smtp address. Both Exchange 2003 and Exchange 2007 rely on that address. if the address specified in "mail" attribute is not one of the addresses "smtp:*" under proxyAddresses, the categorizer will bounce with 5.1.1. I was a bit confused on your process flow for manually modifying the proxyAddresses,mail attributes. Can you explain in a little more detail?

This issue was due to a bug in the Exchagne 2007 RTM version. SP1 solves it. The issue was: When you change the primary proxy address using the Exchange 2007 tooling, the mail attribute was not changed resulting in routing issues. Cheers, Mark