Keep all cells in a column unique? No cells identical
 

Hello. I'm creating a video catalogue list. Each video is being assigned a
unique ID number. Column A is my ID # column. Is it possible to keep every
cell in Column A unique? If so, what would Excel do if I inputted two
identical cell values?

I'm using Excel 2002. Thanks!

Keep all cells in a column unique? No cells identical
 

Click on A1 and:

Data Validation Settings Custom Formula
=COUNTIF(A:A,A1)<2

Then copy A1 down as far as you need

--
Gary''s Student - gsnu200801


"phillr" wrote:

Hello. I'm creating a video catalogue list. Each video is being assigned a
unique ID number. Column A is my ID # column. Is it possible to keep every
cell in Column A unique? If so, what would Excel do if I inputted two
identical cell values?

I'm using Excel 2002. Thanks!