In a VSTO outlook 2010 project I have successfully used the "ContextMenuReadOnlyMailText" to add a context menu to a mail item when the user right clicks on text within the mail item. What is the idmso for the same thing within a Task Item and within an Appointment item?
I found "ContextMenuReadOnlyMailText" in the WordControls.xlsx from the Office2010ControlIDs.
As I cannot find anything in there for Task or Appointment items then maybe they do not exist.