Morning Everybody

Need some advice on a spreadsheet. At work they are currently manually counting things in other spreadsheets to input the data on this one. Now I've managed to get half of the count if functions working but the second half i'm having trouble with. Im trying to get the spreadsheet to count the number of instances within the month of May and every variant i've tried, it keeps returning 0.

I've tried these two methods:
=COUNTIF('[Recruitment Activity Report.xls]AWE - MANPOWER 2012'!$H$10:$H$1459, "???05???")
=COUNTIF('[Recruitment Activity Report.xls]AWE - MANPOWER 2012'!$H$9:$H$176,"May")

Any help would be gratefully received

Thanks again