Date formatting question

[Bob]

I've just upgraded from Windows 98se to XP Pro, and have been using Excel
2000 on both. Since installing XP and reinstalling Excel, however, I've
noticed an annoying quirk which has thrown out the dates of a large set of
sheets created and saved under 98.

The cells are formatted as 'custom', dd/mm/yyyy and previously I have
entered a numeric value - say 1337 - to get the date (late August this
year). Now, however, it seems to resolve to a date in 1903 - a century ago.
I'm sure it's a case of checking a box in the options somewhere, but for the
life of me I can't find what I need to change. Could someone point me in
the right direction, or do I have to update all the cells?

Many thanks.

 

[nobody]

Excel uses either a 1900 or 1904 based dating system with Jan , 1900 being 1
or January 2, 1904 set as 1 depending on the check box set in
tools-options-calculations. I could be wrong but, 1337 seems to be a pretty
low serial number for a date in 2003.

 

[Bob]

I bumped into this extremely useful numbering system for dates when I was
working under Windows 98se, and as I recall, the number 1 represented
January 1st, 2003. Of course I've saved the Excel spreadsheet now, so it's
totally stuffed, unless I can work out how to reset that number 1 to
01/01/2000.