In Sheet2,
Try in B1:
=SUMIF(Sheet1!A:A,A1,Sheet1!B:B)
If you get zero, that means the numbers in Sheet1!B:B are text. Just copy a
blank cell, then select col B in Sheet1, do a right-click > paste special >
add > ok. This should suffice to convert the text numbers to real numbers,
and you should get the correct return from the SUMIF.

Signature
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
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> Hello,
> Got two sheet with the following data:
[quoted text clipped - 10 lines]
> bring back an error.
> Please find me logic to this madness…