Hi guys, All of a sudden nobody in our ORG is receiving emails sent to distribution group. Emails are sent (they show up in the Sent Items in Outlook), they don't generate NDR (yet) nor Delivery Receipt, i cannot track them as they don't show up in the tracking center. All other email flow is OK, so i suspect it is a problem with email routing or distribution queries to AD that are gone wrong,...Our default routing group is sending emails through a smarthost. But as far i know local emails are not leaving the mailbox server so i don't think it is necessarily a problem with the smarthost. On top of that, there is another issue with email forwarding, if users have a forwarding enabled on their mailbox account the forwarding does not work. So it really looks like AD or DNS problem but i cant find what. All dns logs are clean, dns queries on Exchange server is running fine. I have ran a DNS BPA on the DNS server roles and everything is OK as for the AD role Exchange servers are running on version 2003 SP2. I should have added that we prepared last week our AD for e2k10...

Are the groups universal groups?Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."

Hi, Please clarify if the distribution group has been migrated to Exchange 2010. Besides, please try to test the issue with other new created DL. We can try to dump the attribute for problematic DL with working DL. You can follow the steps below to take a LDP dump. Note: The Ldp GUI tool is included when you install Windows Server Support Tools. 1. Double click on LDP.exe 2. Select Connection from the menu and select Connect from the drop down. 3. Server dialog>Enter the Domain Controller and click OK. 4. Select Connection from the menu and select Bind from the drop down. 5. If logged on as an Administrator leave credentials blank and click OK out otherwise enter Administrator credentials. 6. From the menu select View and from the drop down select Tree. 7. Leave the Base DN blank and click OK. 8. Expand the DC from the left frame. 9. Double click on the CN (common name) = Users 10. Select the appropriate distribution group we need to take an LDP dump of. 11. Click Ctrl + N to clear out existing data. 12. Click off user and then click back to the user to refresh new data. 13. From the menu select Connection and then select Save As from the drop down menu.<o:p></o:p> Xiu Zhang TechNet Community Support

No they were not and thats what solved the issue: i converted groups to universal. Thanks Ed