I posted this on the VSTO forum, and they suggested I also post here.

I have an Excel workbook that's part of a VSTO solution. It contains two
named Ranges: OrderDate and ShipDate. When I select either of these cells, I
want the Actions pane to display a user control that contains a label and a
DateTimePicker control. I want the user control to show up in the Actions
pane only when one of these cells is selected, so I have code on the ranges'
Selected and Deselected event handlers to add or remove the control (I'm not
including the code but you can see it in my original post:
http://forums.microsoft.com/MSDN/Sho...teID=1&mode=1).

The solution works fine when I put my cursor on OrderDate and then move to
ShipDate. It also works fine when I move from any other cell to either
OrderDate or ShipDate.

The solution does NOT work when I move from ShipDate to OrderDate. The
control is removed but not added. I added some message boxes and it looks
like the events are firing in the wrong order: The OrderDate_Selected event
fires BEFORE the ShipDate_Deselected event.

(In the OrderDate to ShipDate scenario the events fire as I would expect,
OrderDate_Deselected and then ShipDate_Selected.)

Is this behavior by design? If so why is it that way? (This is a teaching
sample so I'd like to be able to explain why I need whatever workaround I
come up with).

Just so you know, there's nothing special about the workbook. I was able to
recreate on a completely vanilla new workbook/project.