Duplicate those CD/DVDs and how the copies work.
But since you always had the opportunity to duplicate them, why folk don't is a little of a mystery.
And 30 bucks? What a rip off! A new Windows Vista DVD is just 99 or more bucks so what are they thinking.
---> Again, duplicate that media and give it another try remembering to unplug USB and such things.
Bob
I have an HP computer that did not come with recovery discs; it came with a recovery partition and the ability to create ONE set of recovery discs. The discs were created.

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