Hi Yves,

I've cancelled an event for tomorrow due to the rainy weather in Holland.
I went to the Dates page and changed the red icon under Cancelled to the green icon.

I've also deleted a reservation of a member who contacted us that she made a reservation on the wrong date.
In this case I went to the Dates page, clicked on the number of participants of the event.
In this case there was only one participant so I selected her and pushed on the Cancel button on the top.
She also didn't receive a cancellation mail (neither did I as organiser).

Can you look at this problem?

The (new) functionality on contacting participants works fine so that's the way to reach the participants at tis time as a work around.