Outlook 2007 is getting an NDR message when sending email externally

Outlook 2007 is getting an NDR message when sending email externally.  It begins intermittently, some addresses have successful delivery, others do not.  Within three day, all external outgoing mail receives NDR.  The user doesn't experience this problem after disabling cached mode or when using Webmail (Exchange 2007).  I deleted the OST, but that did not solve the problem so I deleted the Outlook profile and created a new one.  This worked for a short time.  Any suggestions?
Who is Participating?
Neil RussellConnect With a Mentor Technical Development LeadCommented:
I dont think that  http://support.microsoft.com/kb/937861 applies unless you have installed 3rd party connectors.

This is often due to corruptions in either the .NK2 file or having contact cards in the local users contacts folder that have an incorrectly formated SMTP: address.

Delete the .NK2 file and check for any contacts for the email address's affected. if found delete and then try sending.
Could you post one of the NDRs?
Neil RussellTechnical Development LeadCommented:
Where is the NDR report? This will give more info on WHY you get them. An NDR is information not just an "Oh i cant do it" message.
Please post example
Easily manage email signatures in Office 365

Managing email signatures in Office 365 can be a challenging task if you don't have the right tool. CodeTwo Email Signatures for Office 365 will help you implement a unified email signature look, no matter what email client is used by users. Test it for free!

brdaellAuthor Commented:
Your message did not reach some or all of the intended recipients.

      Subject:      XXXXXXX
      Sent:      3/10/2011 9:16 AM

The following recipient(s) cannot be reached:

      'user@domain.net' on 3/10/2011 9:16 AM
            None of your e-mail accounts could send to this recipient.
From MS:

To resolve this problem, install Update Rollup 4 for Exchange Server 2007. For more information about Update Rollup 4 for Exchange Server 2007.
brdaellAuthor Commented:
I deleted the NK2 file and will test for a few days.  It's working without problems so far.
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

All Courses

From novice to tech pro — start learning today.