I seemed to have worked around the issue.

Basically, I was filling the calendar with appointments, then adding one of them to the ItemSelection collection to ensure it was highlighted.

If I issue a ItemSelection.Clear, then add the appointment to ItemSelection, the problem goes away.

I'm not sure why it works but it does seem to have cured the problem.

Thanks
Michael.

Hi,

I have a test project that I have put together which shows the problem.
Is there an address I can use to send it to you?

Whilst writing the test project it struck me what the problem probably is - when you issue a Calendar.Schedule.Items.Clear it does not clear the Calendar.ItemSelection collection.

Therefore, when you press delete and it enumerates through the ItemSelection collection to see what needs deleting, it will still have an old reference to an appointment that has been removed from Calendar.Schedule.Items

Let me know if you still need the test project and can email to you.

Thanks
Michael.