This sumproduct formula has failed since the turn of the new year.
I use it on both open and closed workbooks that span from one year to the next, ie 2016 / 2017.

Could you please help me to get it working across the year boundry.

=SUMPRODUCT(('Orders'!$E$13:$E$309)*('Orders'!$D$13:$D$309<=DATEVALUE(TEXT(TODAY(),"dd-mm-")&2016))*('Orders'!$H$13:$H$309='Orders'!$D$2))

Thanks in anticipation.