Hello again,

Thank you very much for help.
Appreciate it.

Can't seem to get it to work, undoubtedly because I'm doing something really
dumb
with this.  Relatively new user.

Would just like to highlight any and all duplicates.

Have my mumbers in Col B, from row 2 to row 483

Entered:
changed to Formula Is.

=if(countif($B$2:$B$483,B2)>1, true,false)

When trying to run it, I get an error msg. that says:

You may not use unions, intersections, or array constants for conditional
formatting criteria.

Any idea what I might be doing wrong ?

Thanks again, Bob
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