No money changing hands and you don't want to be their tech support.
Why not begin the install and after the drive is wiped and you see the XP boot logo, flip the power off, pack it up with what ever CDs you are gifting and send it away.
That's how I do it but if I don't want to part with the XP CD and License (these fetch close to 100 bucks today!) I just install Linux and let it go.
No reason for me to offer lifetime tech support.
Bob
I want to erase the hard drive on my Dell Dimension 8200 and then reinstall just XP and Office so I can give the computer away. I have SP3 installed which prevents me using the original basic XP disc. Do I have to uninstall SP1, 2, 3 before I can use the disc, and are SP2 and SP3 still available for later download (I have a CD for SP1)? Or is there a better way? Will there be problems with Office Professional (I have the original disc for that too)? Thanks.

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