How do I add to a formula to include duplicated entries

[ghrek]

Hi

I have the following formula but im trying to add to it so it marks duplicated entries up as "DUPLICATE" in column F. When I mean duplicate I need it just to mark the 2nd entry onwards as a duplicate and not the first one as thats correct.

Formula so far.

=IFNA(IF(E2=VLOOKUP(A2,WATFORD!A:E,5,FALSE),"OK",""),"N/A")

Any Ideas?

 

[etaf]

where are the duplicates.

I would use a countif($A$1:A1,A1)>1

=IF( countif($A$1:A1,A1)>1, "dublicated","")

if in column a

 

[ghrek]

The duplicates as in column F but will jut use same formula and change A to F.

Many thanks

 

[etaf]

you are welcome