I recently bought a new computer with Windows 7 and the only version of Office I have is 2003. I installed it and everything works except dates in Excel - although they're formatted correctly (and I've tried every single different way of typing them), and they're set in the formatting window to change (and, again, I've tried every choice in there), they don't. When I type 2-digit years the little warning box comes up and asks me if I'd like to change it to a 4-digit year, so it knows it's a date, but it won't change it to whatever I've selected in format cells.

Does anyone have any idea what might be wrong?