Hi Ali

Assuming your column of data entry is A, mark the range of cells you want to
validate
DataValidationCustom in white pane type =COUNTIF(A:A,A1)<2

Change references to suit column required.

--
Regards

Roger Govier


"Ali" wrote in message
...
I have a problem with posibility of repeating data in column. Of course
this
is normal behaviour of Excel, but I need to assure unique data in column.
Is
there a way to do this without an extra effort?