aligahk06
Did You read my the last line?
Did You check that my file?
There were already few duplicates - marked with "DUP". Those
Work Order -values has uses more than once.
With that DataValidation, You can see if that
Work Order -value has used
after You have written it (... but not where? ... not already duplicates )
Formula is basic same as in DataValidation -
[Work Order]
is as A-column from table as well as
@[Work Order]
is that rows
Work Order-value.
What else would You know?
Check
Countif
-function eg from below
How to use the COUNTIF function in Excel to count the number of cells that meet values you set.
support.microsoft.com