Try a soft reset first. Check the manual, the procedure is different depending on the model. Usually there's a small, indented button somewhere on the bottom or back of the device. If that doesn't work, do a hard reset (check the manual again), but you'll lose all your files and programs. You don't have to re-install the OS, even if you've upgraded it. It stays in flash memory so it's invulnerable to the hard reset. If THAT doesn't work, call HP. And that, my friend, is something you don't want to have to do.
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