Grant wrote...
....
So is there a way to do search every row from A1:A100 except for the
current
row?
....

If you mean the formula in, say, A23 would check for instances of the
value of A23 in A1:A22 and A24:A100, then try

=IF(SUMPRODUCT((A$1:A$100=A23)*(ROW(A$1:A$100)<RO W(A23)),"found","not
found")

Alternatively, you could use

A1:
=IF(COUNTIF(A2:A100,A1),"found","not found")

A2 (then filled into A3:A99):
=IF(COUNTIF(A$1:A1,A2)+COUNTIF(A3:A$100,A2),"found ","not found")

A100:
IF(COUNTIF(A1:A99,A100),"found","not found")