Currently I am developing an Add in for Outlook and I have implemented onSend event. Since it is UI-less and it is always triggered, I was wondering is there a way to only trigger it for Appointments not emails? This is because user experience, for them not to have "Add in" triggered when messages are created and sent out.
There isn't a way to restrict On-send to just appointments. One workaround, which I'm sure you are aware of, is to no-op the event handler if the item is a message. This doesn't solve the problem of the add-in running on messages.
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