Leopard upgradeUpgrading to Leopard - Parallels Support Forum: "I'm preparing to upgrade from Tiger to Leopard, and have an install of Parallels 3.0 Build 5584 currently running fine on Tiger OS. I'm monitoring Driver49's post and plan to follow Stacey's recommended sequence of uninstall parallels-upgradeOS-reinstall parallels. I'm also following Joe Kissel's great ebook 'Take Control of Upgrading to Leopard' which contains very clear instructions for preparing your machine for the upgrade. I will have a complete backup clone of the Tiger drive before making the plunge."
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also see ebook "Take Control of Upgrading to Leopard) - Google Search
Take Control Ebooks Home Page