If there is data in rows a1:a10, put this formula into conditional
formatting for cell a1 then use the format painter to copy the conditional
formatting throughout the range of data. (Formatconditional formatting )

=COUNTIF($A$1:$A$10,A1)1



"François" wrote in message
...
I forgot to say that macros are not welcome... cause of security rules.
Sorry !

Hello,
I have to check if a value is found twice in a range and display an error
if
Yes.
Lets suppose a range B3:B29 composed of several values not sorted (for ex
:
250,412,359,1,6,8,45,18,412).
As 412 is found already in second position (and last one) I would like to
change color of Cell B30 from nothing to Red. Of course could be 18 which
appearing twice or more or any other number...

Thanks for you help and creativity !!!