This morning, a bunch of our users are getting error when sending internal emails? But after getting the NDR.. resending the message goes through? Please help!!!! Error message: The e-mail address could not be found. Perhaps the recipient moved to a different e-mail organization, or there was a mistake in the address. Check the address and try again. I track one of the message and this is what it says: 5/11/2009 8:51AM SMTP: Store Driver: Message submitted from store. 5/11/2009 8:51AM SMTP: Message submitted to advnced Queuing. 5/11/2009 8:51AM SMTP: Started message submission to advanced queue. 5/11/2009 8:51AM SMTP: Message submitted to categorizer 5/11/2009 8:51AM SMTP: Advanced queue failed to deliver message 5/11/2009 8:51AM SMTP: Non-Delivered Report (NDR) generated.

Could you please share the NDR sample here for further investigation?Arun Kumar | MCSE - 2K3 + Messaging | ITIL-F V3

Error Message: We have a Windows 2003 Ent. server running Exchange 2003 ent. edition. The following recipient(s) cannot be reached: " John Smith" on 5/11/2009 8:52 AM The e-mail address could not be found. Perhaps the recipient moved to a different e-mail organization, or there was a mistake in the address. Check the address and try again. <servername.domain.com #5.1.0> Thank you in advance for your help!

Are they using outlook cache while sending mail? I mean, just type 2-3 latters of recipient name, it shows the full name from cache, select it and send mail... If so, delete the cache which might have old email address and due to it user are getting NDR. ~ You can remove .nk2 file but which will purge full cache of outlook ~ Write 2-3 letters of user, outlook shows cache info for recipient, hit down button in keyboard which will select the name, hit delete button to delete the cache for particular user.Amit Tank | MVP - Exchange | MCITP:EMA MCSA:M | http://ExchangeShare.WordPress.com

Hi, This code indicates a general categorizer-based failure (bad address failure). An e-mail address or other attribute could not be found in the directory. This issue may occur if contact entries do not have the targetAddress attribute set. Please read the following KB: 5.1.0 NDR when sending or forwarding certain messages with HTML content or MIME-based attachments http://support.microsoft.com/kb/924195 At the same time, I suggest you increase the diagnostic logging level on MsExchange Transport via ESM on that server. If the issue can be reprodureced, check your event log for more information. Please refer to this article Please also try to run dcdiag from a command prompt to check the health status of Domain controller Dcdiag Overview http://technet2.microsoft.com/WindowsServer/en/library/f7396ad6-0baa-4e66-8d18-17f83c5e4e6c1033.mspx?mfr=true Hope this helps. Thanks, Elvis

how about you try sending an email using OWA? As Amit suggested old cache entry may cause the issue... deleting .nk2 file will help here as well.Arun Kumar | MCSE - 2K3 + Messaging | ITIL-F V3

Error haven't come back since that day. User was able to resend email and it went through with no problem? Just strange. Will try out the post from Elvis Wei and monitor server to make sure it's OK. Thank you all for responding to my questions!!! Greatly appreciated!

No problem :) - glad to help.Arun Kumar | MCSE - 2K3 + Messaging | ITIL-F V3