My old HP computer did not come with the XP install disc. I want to install a larger internal HD and also partition it to install Ubuntu so can I use a copy of XP Home and my existing product key to install XP on the new HD?
I would use EASUS disk copy to clone your current disk image onto the new one. Once you reboot using the new HD, then repartition it and install Ubuntu
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btw.. also checkout Neosmart EasyBCD to manage the multi-boot envirnnment if needed