Don’t insert or delete a cell (or at least be very careful)

Have you ever had a formula that was perfect, and suddenly, for no apparent reason it looks to the right or down? Perhaps you did this?

To follow along go to Inserting a Cell HEH

Similarly, have you ever done something and suddenly one or a few (not all cells) have a REF error. The REF error cells need to be fixed, but watch out for the cells to the right or below as well.

To follow along go to Deleting a cell HEH