[Cpl. Shrike]

Well it also depends on wich version of XP.
I know some versions did the upgrade thingy.
If it doesn't do upgrade then you'll have to reinstall all your programs.
The programs are still on your harddisk but all the registry and entries are gone.
Some programs will work if you make a new shortcut. but more advance programs depend on the registry to work.

So 98 to XP is no problem without formating your drive but you'll probably need to reinstall programs.

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