One of my users has this problem also. It must be to do with the send on behalf of option, as my user had the affected recipients in their AD send on behalf of field also. Did you check the delegates tab on the clients outlook options? I believe that can do the same thing. I am going to try removing the send on behalf in AD, although the user wants that setting they would rather not waste other peoples time by having them turn up to meetings thaey dont need to be at! Will let you know how i got on. It is very strange that it would do this! I am using SBS2003 running exchange.

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