One way ..
Assuming data in A1, down
Put in B1:
=IF(COUNTIF($A$1:A1,A1)>1,"Duplicate","")
Copy down as far as required

Signature
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
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> What formula do I need to type in Column B cells to identify the duplicated
> entry (only the second entry)
[quoted text clipped - 10 lines]
> Watch
> Toy Duplicate