Meeting recipient deleting Outlook invite causes cancellation email to all invitees

Employee uses Notes r6.5.5. Receives meeting invite from external Outlook user. (Not yet known if Notes user accepts meeting or not). Notes user deletes meeting and a meeting CANCELLATION email is sent to all meeting invitees who click OK and the meeting gets cancelled.

copied from IM session:

… I get a lot of ‘meeting invitations’ from people that use outlook. If I accept the meeting, it puts it on my calendar. That’s fine. However… if I EVER want to delete it, it sends a

… meeting cancellation to ALL people copied.

… I have spent weeks trying to remove that entry with out broadcasting all invitees that I am cancelling the meeting.

… Before I realized this. I cancelled about three ‘recurring meetings’ in customer’s system. About 10 people replied saying OK. You can imagine my embarrassment that I cancelled project meetings.

Any clues?

TIA