We have some users that receive this message when sending meeting requests
or updated meetings to outside recipients.  We use Exchange 2003 and Outlook
2007.  Regular emails to the same recipients are sent without a problem.

When I look at the Queues on the server, I see the message(s) in the "Retry"
state and sit there until the retry time expires.

Has anyone experience this problem?  Any help is appreciated.

Thanks!

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