If I understand you correctly, you'd like to determine the number of
duplicate order numbers for a particular customer.

So, assuming that A2:C8 contains your data, enter the customer of
interest in, let's say, E2. For this example, we'll enter United. Then
use the following formula...

=IF(E2<"",SUMPRODUCT(--(B2:B100=E2),--(MATCH(C2:C100&"",C2:C100&"",0)<R
OW(B2:B100)-ROW(B2)+1)),"")

According to your table, the formula will return 1. And if we change
Job Number 7 to 3, the formula will return 2.

Does this help?

In article ,
johncassell
wrote:

Thanks Domenic, I appreciate the reply but the doesnt seem to be
working.

Heres an example:

Job Number Customer Order Ref/Number
1 United 1
2 Hoyer jimmy
3 United 1
4 Hoyer dave jones
5 Deltank 75858
6 United 2
7 United 3

The result of the formula should be 1, i.e. there is 1 order number for
United that has been duplicated and if I changed the order number for
job 7 to 2 the result would be 2.

Thanks again for the replies, this is really baffling me!!!

John