Meeting Requests and NDRs

[OregonSteve]

Greetings-

Single Server with about 700 users. A troublesome issue started happening a few weeks ago:

Scenario One: The user sends out a meeting request to a System Distribution List. User gets back three NDRs from users who aren't even in the system any longer; no user account, no contact.

Scenarion Two: Another user replies to meeting requests from one specific person and chooses Edit Response Before Sending. She immediately gets an NDR from someone other than the Sender of the meeting request, someone who's also been deleted from the system.

Are these related? Seems so to me. But how? And, more importantly, how can I fix it?

Thanx
OregonSteve

"..You should never, never doubt what nobody is sure about." -Willy Wonka

 

[OregonSteve]

SOLUTION:

The NDRs were a result of "orphaned" user objects in AD. When a user leaves the organization, the account is deleted. But if that user was added as a delegate to an email account, there remains a residual entry (NT User:012435-23-23456, for example). So when a meeting request is sent to or from an account with this "Ghost" entry it results in the NDR.

So this spawns another question: Why are these being left behind by AD. Is there a Tombstone setting somewhere I have to turn on or reenable or something?

Thanx
OregonSteve

"..You should never, never doubt what nobody is sure about." -Willy Wonka