My add-in can add data validations to a number of cells in different columns
of a worksheet. When the users click in these cells they get this nice
little yellow box by the cell that contains information about the
validation.

So far so good.

The problem is a user who dragged this little yellow box to a different
point on the worksheet. Once they do this, Excel never moves the yellow box
again. It doesn't matter what cell the user clicks into, the contents of
the box changes but its location is now frozen.

I tried protecting the worksheet but that doesn't prevent the user from
moving the box.

Is there anyway in my code that I can intervene in this process? Some event
or method that would allow me to control the placement of these yellow
boxes?

TIA

josh