I can't get into your other post for some reason so I'll give you my answer to your question on datediff here:

'my guess (I'm not sure where it starts counting)
'thurs or Mon...the stuff is hard reading..


'assuming there are 5 working days in each week

Dim nDateDiff As Variant
nDateDiff = DateDiff("w", Date, "20/10/2000", vbMonday) * 5
x = nDateDiff
MsgBox x