I need a formula to calculate the total number of hours and minutes between two date/time values. In addition the calculation must ignore the hours between 4:00AM and 10:00AM, include all weekends and holidays and have the ability to span multiple days.

I have tried simple subtraction but Excel doesn't seem to allow for more than a 24 hour difference. I also tried a solution I saw on http://www.mvps.org/dmcritchie/excel/datetime.htm but can't seem to get it to work either.

Any help appreciated.

Thanks -Rob-