This one is really stumping me...

I have a spreadsheet that contains a column of dates, the next column should
calculate that date plus 1 day. I only want workdays.

My formula is: =WORKDAY(A5,1)

I'm getting:

Column A Column B
Open Date/Time Close Date/Time
09/19/2006 2:19 PM 09/20/2006 12:00 AM
08/18/2006 12:41 PM 08/21/2006 12:00 AM
11/01/2006 8:25 AM 11/02/2006 12:00 AM
08/12/2006 11:40 AM 08/14/2006 12:00 AM
10/07/2006 12:20 PM 10/09/2006 12:00 AM

The dates in Sept and Nov are working. The dates with Aug and Oct are not.
(They are adding more than 1 day.) They all have the same formula and the
formats are all the same.

What could I be missing here?

Thank you,

Rachel