I'm using Excel custom data validation to restrict entry in D2, if D1 is 0 or blank. The formula =D1>0 works just fine if D1 is a number greater than 0, but if DI is blank, the restriction does not work. Put another way, I want a blank cell In D1 to be treated as if it was a zero. I've tried removing the checkmark in the box beside Ignore Blank in the validation criteria window but that does not help. . Help for this formula please?