If you can't prove to Microsoft that you own a legal copy, then I would
assume yes, you'll have to buy a new copy. Unfortunately, that's not going
to be easy if you're still running Windows 98: the current version of Office
(Office 2003), which is the only version Microsoft sells anymore, will not
run on Windows 98.
If you have more questions, I'd recommend asking in a newsgroup related to
Excel. This newsgroup is for questions about Access, the database product
that's part of Office Professional.
