My sheet is "protected". The user is only allowed to select
locked or unlocked cells. If a user tries to double click on any cell
or change data, Excel shows the following message box:

"The cell or chart that you are trying to change is protected and
therefore read-only."

Does anyone know if it's possible to override this default message
box? It would be nice if I could display my own custom message
box, or run my own subroutine if a user tries to change data on a
protected sheet. I doubt it's possible, but I just want to check if
anyone here knows how to do this??

Thank you!

Robert