What exactly didn't work? I tested it and think it's OK.
JM


"Browny" wrote in message
...
Hi Joerg

I think you'r on the right track, but it didn't work
--
Browny


"Joerg Mochikun" wrote:

Hi Browny,

use this conditional formatting formula for C1 and then copy format down
to
C100:
=SUMPRODUCT((($A$1:$A$100)&($C$1:$C$100)=A1&C1)*1) 1

This will highlight cells in column C if the invoice number and the
company
name in column A appear more than once. If you also want to highlight
company names, you could apply the same conditional format for column A.

Cheers,
Joerg Mochikun

"Browny" wrote in message
...
Thanks Alderran
I agree with the data base. However it's a company spreadsheet. Too
much
data to change now.
i have many invoices from the same companies but i want to verify they
only
use the 1 invoice number. Can you help?
--
Browny


"alderran" wrote:

You should put this data into an Acess database. You could make the
company
name and the invoice number a key and allow no duplicates.
Spreadsheets
are
definitely not good databases.

"Browny" wrote:

I have 'company name' in A1:A100 & 'invoice number' in C1:100 and
ongoing.
I wish to highlite (conditional format) the company name & invoice
number if
they have been duplicated. I almost paid someone twice.

Many thanks

Browny