SUMIFS Not Blank Criteria

Hello,

I am trying to improve a successful SUMIFS formula by adding an additional criteria.

It already totals figures from column F based on a common cell value in column H, and a specified word in column V. I now also need it to only total those figures if the cell in column N is NOT blank.

The original formula that works is this:
=SUMIFS('[Budget Journals 1112.xls]GBP'!$F$4370:$F$65536,'[Budget Journals 1112.xls]GBP'!$H$4370:$H$65536,$A8,'[Budget Journals 1112.xls]GBP'!$V$4370:$V$65536,"PAY EXPENDITURE")

The new one needs to be something like:
=SUMIFS('[Budget Journals 1112.xls]GBP'!$F$4370:$F$65536,'[Budget Journals 1112.xls]GBP'!$H$4370:$H$65536,$A7,'[Budget Journals 1112.xls]GBP'!$V$4370:$V$65536,"PAY EXPENDITURE",'[Budget Journals 1112.xls]GBP'!$N$4370:$N$65536,NOT(ISBLANK))

...but I'm having no success with that.

Many thanks in advance for your time.

Phil