HI All, Look like No MS expert have the answer to this issue.... I have a shared mailbox called "Helpdesk" add all the helpdesk users to Security group called "Helpdeskmailboxaccess" EMC- Add full permission to "Helpdeskmailboxaccess" and SEND AS for "Helpdeskmailboxaccess" But users try to send FROM : helpdesk@mycomp.com got the NDR Only works if i select from GAL not from the autocomplete. ( Not a solution) no users or group belong to protective groups remove re add the send as in AD no effect. check the permision from cmdlet -all ok. So user got the issues sending from? Any one got the answer? AS

Hi, Could you please post the NDR - it might tell us whats wrong. Leif

Yes please post the NDR message. Also try deleting the address from the Outlook NIC cache and then try again. Maybe a legacydn issue somehow?Chris Morgan

Delivery has failed to these recipients or groups: user@domain.com You can't send a message on behalf of this user unless you have permission to do so. Please make sure you're sending on behalf of the correct sender, or request the necessary permission. If the problem continues, please contact your helpdesk. Diagnostic information for administrators: Generating server: user@domain.com #MSEXCH:MSExchangeIS:/DC=com/DC=domain:EXGORGEXG01[578:0x000004DC:0x0000001D] #SMTP# As i sain Its works only Open from GAL.

Hi, Since this issue not occur when you choose from GAL, I think permission you sat on "Helpdesk" is right. I suggest you use OWA, manually input the email address (helpdesk@mycomp.com) to have a try. If this issue not occur when you test in OWA, go to remove autocomplete in Outlook, then input the email address (check name for it) to have a try. Delete a name from the Auto-Complete list http://office.microsoft.com/en-us/outlook-help/delete-a-name-from-the-auto-complete-list-HA010355568.aspx 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

user@domain.com #MSEXCH:MSExchangeIS:/DC=com/DC=domain:EXGORGEXG01[578:0x000004DC:0x0000001D] #SMTP# As i sain Its works only Open from GAL. Appears by using the Outlook NIC cache it's grabbing the incorrect information, specifically the Exchange Legacy DN. As Evan and I stated, deleting that cache should clear up the problem. To resolve the issue globally you would have to add the old Exchange Legacy DN as an additionaly X500 address to their prospective accounts. Then you would not have an Outlook nickname cache issue as they would be able to resolve those addresses in the new forest.Chris Morgan

Hello, Any updates on this issue? 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

HI Evan, I can send from OWA and select from the GAL. Also clearing Auto-Complete list/ NK2 didn't help. But Chris point the issue. We have migrated from Source Domain to Target domain and add the x500 address. So how do i add the secondary and will course any issues? also found that outside users also get the NDR sending to the email that they sending before?but i can send new email from my gmail no problem? Look like finding source email address? So how do i fix this issue? ====================================== NDR Diagnostic information for administrators: Generating server: <http://ex04.source.com> ex04.source.comhttp://ex04.source.com mailto:rnows@target.com> #< #4.4.7 smtp;550 4.4.7 QUEUE.Expired; message expired> #SMTP#

HI, I just found the X500 address but it got source domain details? also found this http://blog.scottlowe.org/2007/02/15/preserving-nickname-cache-in-exchange-migrations/ AS

You mean when users reply to the old emails, they will get NDR, right? If so, you can just add the x500 address on your mailbox. Cannot Reply To Old Emails Or Modify Old Calendar Items After PST Mail Migration http://blogs.technet.com/b/sbs/archive/2009/05/21/cannot-reply-to-old-emails-or-modify-old-calendar-items-after-pst-mail-migration.aspx 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