What is wrong with this SUMIFS formula?

[IloveExcel12]

I'm trying to calculate sales based the customer's start date, and between certain months. Every SUMIFS formula is giving me numbers higher than my data sheet. Formula below:

=SUMIFS('[ConversionEnd Data.xlsx]Page1_1'!$D:$D,'[ConversionEnd Data.xlsx]Page1_1'!$A:$A,$B5,'[ConversionEnd Data.xlsx]Page1_1'!$C:$C,">="&$I5,'[ConversionEnd Data.xlsx]Page1_1'!$C:$C,"<="&$J5)

First criteria is the customer's account number, second are the dates the customer made the purchase, being greater than or equal to the start date, and then less than or equal to the end date. I can't see why this will be giving me wrong numbers, not sure if anyone else does.

I checked to make sure everything is in date format and it already was.

 

[Aladin Akyurek]

Does the following behave different?

=SUMPRODUCT('[ConversionEnd Data.xlsx]Page1_1'!$D:$D,--('[ConversionEnd Data.xlsx]Page1_1'!$A:$A=$B5),--('[ConversionEnd Data.xlsx]Page1_1'!$C:$C>=$I5),--('[ConversionEnd Data.xlsx]Page1_1'!$C:$C<=$J5))​

Note. Try to avoid referencing whole columns for efficiency reasons.

 

[IloveExcel12]

Does the following behave different?

=SUMPRODUCT('[ConversionEnd Data.xlsx]Page1_1'!$D:$D,--('[ConversionEnd Data.xlsx]Page1_1'!$A:$A=$B5),--('[ConversionEnd Data.xlsx]Page1_1'!$C:$C>=$I5),--('[ConversionEnd Data.xlsx]Page1_1'!$C:$C<=$J5))​

Note. Try to avoid referencing whole columns for efficiency reasons.

Nope giving me the same numbers... No idea what's going on.

 

[Aladin Akyurek]

Nope giving me the same numbers... No idea what's going on.

Try to reduce the ranges you are looking at, to 10 rows for example, and analyze where your logic fails to produce the expected result.