I have one user that randomly receives NDRs when she sends out meeting requests to a group of users. The problem is that the NDRs refer to a user that is no longer in the system. I've checked forwarding rules on all the users that receive the e-mail and none have a rule forwarding e-mail to this non-existent user. I've also checked the delivery options for each user in the Exchange Management Console and none have forwarding address in their account. The NDR looks like this: Delivery has failed to these recipients or distribution lists: Recipient The recipient's e-mail address was not found in the recipient's e-mail system. Microsoft Exchange will not try to redeliver this message for you. Please check the e-mail address and try resending this message, or provide the following diagnostic text to your system administrator. _____ Sent by Microsoft Exchange Server 2007 Diagnostic information for administrators: Generating server: HTSERVER.DOMAIN.COM IMCEAEX-_O=ORGANIZATION_OU=EXCHANGE+20ADMINISTRATIVE+20GROUP+20+28FYDIBOHF23SPDLT+29_CN=RECIPIENTS_CN=Recipient@Domain.com #550 5.1.1 RESOLVER.ADR.ExRecipNotFound; not found ## Original message headers: Received: from CCR1.DOMAIN.COM ([10.1.1.1]) by HTSERVER.DOMAIN.COM ([10.1.1.3]) with mapi; Thu, 12 May 2011 08:07:41 -0700 Content-Type: application/ms-tnef; name="winmail.dat" Content-Transfer-Encoding: binary From: Sender To: Recipient IMCEAEX-_O=Organization_OU=EXCHANGE+20ADMINISTRATIVE+20GROUP+20+28FYDIBOHF23SPDLT+29_CN=RECIPIENTS_CN=Recipient@DOMAIN.COM Date: Thu, 12 May 2011 08:07:41 -0700 Subject: Somebody - out Thread-Topic: Somebody - out Thread-Index: AcwQtlRSko0jFB5dS+6fYkDq50R4tA== Message-ID: <4E93E52CA1C439468263E27BA8EC3C9AAC99207036@CCR1.DOMAIN.COM> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-Auto-Response-Suppress: DR, OOF, AutoReply X-MS-TNEF-Correlator: <4E93E52CA1C439468263E27BA8EC3C9AAC99207036@CCR1.DOMAIN.COM> acceptlanguage: en-US x-tm-as-product-ver: SMEX-10.0.0.4152-6.500.1024-18130.006 x-tm-as-result: No--34.135600-0.000000-31 x-tm-as-user-approved-sender: Yes x-tm-as-user-blocked-sender: No MIME-Version: 1.0 Heriberto Contreras

Delegate. Someone in the list has a delegate on their mailbox. That delegate is probably a user who has had their mailbox deleted. Simon.Simon Butler, Exchange MVP Blog | Exchange Resources | In the UK? Hire Me.

Orphaned delegate like Sembee mentioned. Accepting or denying a meeting request causes a "5.1.1" non-delivery report in Exchange Server http://support.microsoft.com/kb/312433James Chong MCITP | EA | EMA; MCSE | M+, S+ Security+, Project+, ITIL msexchangetips.blogspot.com

Hi, 1. Check if the user's offline address book is updated. (use online mode or OWA to test) 2. Check the member of distribution group. Sometime the mailbox is still in the distribution group even though the mailbox has been disabled. Get-DistributionGroupMember -Identity groupNamePlease remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

UPDATE: Isolated the user mailbox that is causing the NDR, let's call him User X. I am able to duplicate the NDR by sending meeting request to User X. I found permissions assignment in User X's calendar for the non-existend user, sadly enough removing the permissions did not solve the problem. User X does not have any delegations setup in his mailbox. Next move is to delete local mail profile and cached mail files. I will post update after that has been completed. Thanks all for your suggestions so far.Heriberto Contreras

How long did you wait? It can take a little while for Exchange to catch up. A lot of permission type settings are cached and can take two hours before they are live. It is also not unknown for the delegate to not come correctly and for an entry to be left in the domain which has to be removed via adsiedit.msc. Deleting the Outlook profile and cached files is a waste of time, because this is a server issue - has nothing to do with Outlook. Simon.Simon Butler, Exchange MVP Blog | Exchange Resources | In the UK? Hire Me.

It could also be a corrupt rule in user X's mailbox. If the issue still persists after waiting some time, log into user outlook by doing outlook /cleanrules. This will whack all his current rules as well as any corrupted rules including the delegation. Back his rules up as this will whack all of them.James Chong MCITP | EA | EMA; MCSE | M+, S+ Security+, Project+, ITIL msexchangetips.blogspot.com

I waited a full day from the time the calendar permissions were removed to test again and the problem persists. I too thought that it might be a rule but User X does not have any rules configured. I thought that I could clean up the delegation, or whatever is causing the problem, via ADSIEDIT but I'm not sure where the setting would be. Heriberto Contreras

It will be on the properties of the user, and is something like msexchdelegate. It has the word delegate in there, so finding it is quite easy when you have the properties list of the user. Simon.Simon Butler, Exchange MVP Blog | Exchange Resources | In the UK? Hire Me.

I checked the user properties in ADSIEDIT and did not see any entries in either of the attributes that looked like the place for delegates to be in, msExchDelegateListBL and msExchDelegateListLink. I did find a second calendar object in User X's mailbox, which did not have any appointments, looks like it was residual from when we migrated from GroupWise. The duplicate calendar object was deleted but that didn't change anything either. Still fishing for ideas. Thank you all for your suggestions so far. UPDATE: The name of the atribute is publicDelegates Heriberto Contreras

Hello, 1. Ask the user if they are "re-using" an old appointment. An old appointment may have the legacyDN for the deleted user as one of its properties. 2. Verify that the user is not using a distribution list that contains the old recipient. Note I said list not group. 3. Confrim that the user does not have the old user in their contact list. Bill

User did have the non-existent recipient in his contact's list. Deleting the contact took care of the problem Thank you all for your suggestions.Heriberto Contreras