Hi, I had a mailbox that had problems. I used exmerge to export the mailbox contents to a pst, removed the mailbox and cleared the exchange atributes, recreated the mailbox and imported the pst via exmerge. When the user modifies a meeting, and sends updates to removed or added participants, she receives a ndr. The ndr does not show in eventviewer. The user gets the following ndr and its only for mail sent from meeting related work. She can send normal mail to all these users. You do not have permission to send to this recipient. For assistance, contact your system administrator. MSEXCH:MSExchangeIS:/DC=xxx/DC=xxxxxx:ExchangeServer01 Could it be because I removed all exchange attributes from the account too?

Hi,Please try to use MFCmapi.exe to check the value on PR_SENT_REPRESENTING, it should point to the organizer.Also we can check value on attribute listing below:PR_LAST_MODIFICATION_TIMEPR_LAST_MODIFIER_NAMEMicrosoft Exchange Server MAPI Editorhttp://www.microsoft.com/downloads/details.aspx?FamilyId=55FDFFD7-1878-4637-9808-1E21ABB3AE37&displaylang=en Cannot Modify or Cancel a Meeting Request That Originated from a Deleted User's Account http://support.microsoft.com/kb/279428 Regards,Xiu

I agree with Xiu's suggestion and in addition you can check and try the below mentioned steps as well.Is this happening for all the meetings or for any specific meeting?,Doubt there must be corruption in the mailbox calendar,Is this for all the users?How about i extracting that meeting request to PST, delete it from calendar and put the meeting request back and check?We can try running isinteg on the database to check if there is any logical corruption.Arun Kumar | MCSE - 2K3 + Messaging | ITIL-F V3

I will try what you have recommended and come back to you either today or tomorrow at the latest.

PR_LAST_MODIFICATION_TIME LowDateTime - 0x6B7EAA3C HighDateTime - 0x01C9C8F9 Date: 06:36:33.264 PM 4/29/2009 PR_LAST_MODIFIER_NAME I dont have this value, but I do have PR_LAST_MODIFIER_SID Cb - 0x0000001C = 28 Bin - 0105000000000005150000000AEE8A360E80E270B859901D92370000

This is happening for all meetings that existed before i extracted the mailbox to a pst, deleted the mailbox, cleared exchange attributes and then recreated the mailbox and reimported the pst. This happens for all delegates and they only get the NDR for existing meetings and new meetings are unaffected.

I exported the calendar to a completely different mailbox, and when I modify the meetings it tells me I dont have the permissions to send the updates. How can I totally take over a calendar? New meetings work fine even when exported to a different calendar.

Okey.. Lets do one thing more here.. If you're using Enterprise server, create another mailbox store, move the effect users mailbox to that store and check if that works.Cause i believe this is some kind of curruption in the mailbox/database? when did this happened? did you restored the database by any chance?Arun Kumar | MCSE - 2K3 + Messaging | ITIL-F V3