try this

Assumed Col A - Month
Col B - Employee
Col C - IC
Col D - Dept
Col E - Duplicate

in cell E2 put this formula and drag it down

=IF(COUNTIF($B$2:$B$10,B2)1,IF(COUNTIF($D$2:$D$10 ,D2)1,"X",""),"")


On Feb 3, 12:25*pm, sragor wrote:
hi,
I have the data as follow:
Month *Employee * * *IC * * * * *Department * * * * * *
Jan * * * Tom * * * * * * 123 * * * * HR * * * * * * * * * * * * * * * *
Feb * * * *Tom * * * * * *123 * * * * *HR * * * * * * * * * * * * * * * * *
Mar * * * Tom * * * * * * 123 * * * * *IT * *

Expected result: Same department but different month is a duplicate. Same
person but NEW department is NOT a duplicate.
Month *Employee * * * *IC * * * * * Department * * * * * * *Duplicates
(marked with 'x')
Jan * * * Tom * * * * * * * 123 * * * * HR * * * * * * * * * * * * * * * *
Feb * * * *Tom * * * * * * *123 * * * * HR * * * * * * * * * * * * * *x
Mar * * * Tom * * * * * * *123 * * * * *IT * * * * * * * * * * * *

To check for duplicates, I did... =IF(COUNTIF(C$2:C20,C20)1,"x","") * where
column C *is the unique IC number. How do i make sure that my guy in a new
department is not treated as a duplicate because the current function will
result in all but only one to be duplicates.