On Wed, 11 Nov 2009 19:03:02 -0800, Bob Reddy
wrote:

I copied a xls worksheet from an Excel 2003 to a new PC with Vista and Office
7. The worksheet has over 7000 rows, one of which contains dates. The dates
have shown up a 5 digit numbers. I formatted the date column to show dates
as 1/1/09 formats. Only 15% to 20% of the cells changed to the 1/1/09
format. The rest seemed to be locked in the 5 digit number format and can't
be changed. I tried to delete a few cells and manually type in dates. The
cells remained as 5 digit numbers.
Any sugesstions would be appreciated.

Make sure the sheet is unprotected, and highlight the entire column
when you perform the format operation.