Hello,
I would do that differently:
Dim strFromDate, strToDate As String
strFromDate = "12/1/2011"
strToDate = "12/22/2011"
Dim toDate, fromDate As DateTime
toDate = DateTime.Parse(strToDate, New CultureInfo("en-US", False))
fromDate = DateTime.Parse(strFromDate, New CultureInfo("en-US", False))
Dim nbWeeks As Long
nbWeeks = Math.Abs(DateDiff(DateInterval.Day, fromDate, toDate) / 7)
Valery.