Over at hp.com many of the models have restore instructions. Supply the model model (please get the model and not the series) so others can look if you don't find it.
Bob
Bought an HP desktop at an estate sale and it will not boot because it is protected by a password that no one knows. It came with all the operating system discs. It has Vista Home Premium loaded. How can I format the drive and reload the operating system?

Chowhound
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