Everytime I click Update when I open the Excel document the data is lost. I link to some external documents. If I open those documents the data reappears. The formula with the link looks something like this:
=SUMIF('\\adress\folder\folder\folder\folder\folder\folder\folder\folder\[Linia1.xls]BD'!$A$2:$A$65536,A19,'\\address\folder\folder\folder\folder\folder\folder\folder\folder\[Linia1.xls]BD'!$AR$2:$AR$65536)