Thanks for your response. Yes, I also posted in one of the Exchange groups.

Brett

"Milly Staples [MVP - Outlook]" wrote:

Have you posted this to an Exchange group?

--
Milly Staples [MVP - Outlook]

Post all replies to the group to keep the discussion intact. All
unsolicited mail sent to my personal account will be deleted without
reading.

After furious head scratching, LH - Brett asked:

| Recently we began seeing an increase in Delay and Failure notices in
| relationship to meeting requests with outside persons. Specifically,
| if we include someone that resides on an Exchange 2007 server
| (outside) the meeting will surely generate a delay then subsequent
| failure.
|
| If the user on the Exchange 2007 server creates the meeting, we get
| it just fine. If we then try to edit the meeting; new time, new
| people or resources, the request will not get back to the originator
| and we will receive a delay/failure.
|
| Now, if we send a meeting to someone on an Exchange 2003 box, no
| problems.
|
| Us:
|
| Exchange 2003 SP2
| Windows 2003 SP1
| Outlook 2007
| Outlook 2003 SP1 & SP2
|
| Them:
| Exchange 2007
| Windows 2003 SP2
| Outlook 2007
| Outlook 2003 SP2
|
| Tried:
| Disable Spam filters
| Disable AV
| Routine Exchange DB Maintenance
|
| Message in Exchange Queue
| "Unable to open message for delivery"
|
| Message in NDR
| "Could not deliver in the time specified"
|
| Any Ideas?