If Order is really single characters, then

=COUNT(1/FREQUENCY(IF(A2:A7=40,IF(B2:B7=1,IF(C2:C7<"",CODE (C2:C7)))),IF(A2:A7=40,IF(B2:B7=1,IF(C2:C7<"",COD E(C2:C7))))))

which is an array formula, it should be committed with Ctrl-Shift-Enter, not
just Enter.
Excel will automatically enclose the formula in braces (curly brackets), do
not try to do this manually.
When editing the formula, it must again be array-entered.

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HTH

Bob


(there's no email, no snail mail, but somewhere should be gmail in my addy)



"Lene S" wrote in message
...
Hi
I need Excel to count the unique appearances based upon two criterias.

The columns needed is:
Week Machine Order
40 1 A
40 1 B
40 1 A
40 2 C
41 1 D
41 1 A

How do I count the unique numbers of orders in week 40 and for machine 1?
In
this case 2.

Thanks in advance
Lene S