Hi,

I'm looking for a way to make a "pop-up" appear when a particular cell is
left blank.

For example,

If cell 1 in Column A is filled with the term "Collateral" (picked from
dropdown), then cell 1 in Column D must be filled. I'm looking for a formula
or macro to make this mandatory so that people filling out the spreadsheet
cannot ignore column D when that specific entry is used in column A.

Any help would b great. Tnx!
srain