|This webpage has instructions and links to free utilities (two are from HP, so should work for you). |
Try tapping the ESC Key as soon as you power on the unit.That (at least on some "Minis") will take you to a Startup Menu. Press the F11 Key to launch System Recovery. Follow the on-screen instruction from there. That should take the machine back to default factory settings. <color="red">CAUTION!!!</color> This will probably mean losing any files that haven't been backed-up.
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