Can anyone tell me why I get an error (#VALUE) with
=SUMIF('C:\[doc.xls]sheet'!$M$4:$M$1000,"page",'C:\[doc.xls]sheet'!$G$4:$G$1000)

and when I use this I get correct answer :
{=SUM(IF('C:\[doc.xls]sheet'!$M$4:$M$1000="page",'C:\[doc.xls]sheet'!$G$4:$G$1000))}

Is SUMIF not able to work on multiple workbooks?