sumproduct additional information for adding another criteria

=SUMPRODUCT(--(H17:H1204=M1),--(J17:J1204<>"Paid Account"))

The above formula was given to me earlier and works perfectly, however I now need to add another criteria to it. At the minute it is counting the number of sales within the given data range aslong as the data contained matches that of cell 'M1' but not if the phrase "paid account" is displayed in the data range of column 'J'.

I also want now for it NOT TO add up the sales if there is a blank within the corresponding cells of the data range B17:B1204 aswell.

If anyone can provide this formula it would be appreciated and also explain why dashes and brackets are used so then I might be able to learn why the given formula works.

Many thanks in advance.

Try this, and let me know if it works:

=SUMPRODUCT(--(H17:H1204=M1),--(J17:J1204<>"Paid Account"),--(B17:B1204<>""))

Yea that works fine. Thanks.

I didn't realise you can just keep adding arrays and the number of brackets contained remains the same.