Hello,

Don't enter them as array formulas. It is not necessary.

You have a #VALUE! error in range C1:C8647, I presume. Have a look into
these cells and eliminate that error.

Finally I suggest to use
=SUMPRODUCT(--([RetaileastEfficiency.xls]RetaileastEfficiency!$D$1:$D$8647=C$*2),--([RetaileastEfficiency.xls]RetaileastEfficiency!$B$1:$B$8647=DATE(2006,*4,1) ),--([RetaileastEfficiency.xls]RetaileastEfficiency!$B$1:$B$8647<DATE(200*6,5,1)) )
to count and
=SUMPRODUCT(--([RetaileastEfficiency.xls]RetaileastEfficiency!$D$1:$D$8647=C$*2),--([RetaileastEfficiency.xls]RetaileastEfficiency!$B$1:$B$8647=DATE(2006,*4,1) ),--([RetaileastEfficiency.xls]RetaileastEfficiency!$B$1:$B$8647<DATE(200*6,5,1)) ,[RetaileastEfficiency.xls]RetaileastEfficiency!$C$1:$C$8647)
to sum (NOT array-entered). But: Your original formulas should work
after elimination of the error value(s).

Regards,
Bernd