I am trying to use a function to evaluate when a course is due. In column D
there may or may not be a date listed. I'm using this formula in to evaluate
if the course is due to be renewed.

=IF(DATE(YEAR(D3)+3,MONTH(D3),DAY(D3))<=TODAY(),"d ue"," ")

The problem arises when D3 is blank. It is still evaluating the blank cell
as a date, 01/01/1907 and returning "due" because it is less than today.

If D3 is blank I need the formula to return an empty string, which I thought
the above did.