You posted a variation on this question at MrExcel here

I suggested using NETWORKDATS.INTL function (available in Excel 2010 and later) because that function will allow you to count all days except those you list as exceptions, so matching my suggestion to your workbook perhaps try variations on this formula

=NETWORKDAYS.INTL(C2,D2,"0000000",'Dates to exclude'!A$1:A$8)-1+MOD(D2,1)-MOD(C2,1)

....although I'm not really clear what result you are expecting when D2 < C2