Hi

Practically the only event you can use is OnChange - which is fired AFTER you move cursor from the cell you did change - not very easy at least. When you can somehow to get information, what was the last cursor location before current one, and is this cell empty now, then maybe you can take a step back, when you check No - but not very likely.

And remember - the OnChange event is fired whenever you make any change on any worksheet! So your workbook will be slow down considerabely.