I need help,
I am trying to write a module that will change the value
of a cell when a different one is selected.

For example - user clicks on B1 (only selecting the cell -
no change of value) and C1 value would then show "Y" - if
B1 were clicked again then C1 would change to "".

I can figure everything out except how to make excel/VBA
recognize that a cell has been clicked.

Thanks for any advice!