I have two cells B10 and B11
I need to check both cells for valid dates prior to calculating the difference between the two.
What is the best in cell formula to check for a valid date. e.g. blanks, '-' , or NA, '2342jflsd'
Cell B9 will have the formula for data checking and also will be the cell that holds the number of days difference between the two
thanks for your time in advance!