It really isn't as simple as 'upgrade' or 'wipe it clean'. There are companies with software that literally don't run on anything but XP. The devs of said software don't exist any more, so you can't really just say "hey, upgrade". Hell, a $multi-million , multinational company does this just here in Iowa. John Deere, perhaps you've heard of them?
It's never as simple as "just upgrade" or "just reload". In the case of JD, they've got systems that cost more in maintenance fees than they do to upgrade (as in hardware), and they're just a hardware problem or two away from total combustion. However, the budget is not there for an upgrade the size you're talking about.
Tom Whiting, WHMCS Guru
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