My notebook was completely locked out from finishing a start up. The BSOD alert critical process died was constantly displayed. Safe Mode would not work. Win Recovery would not work. Win Reset would not work. System Restore would not work. I followed all the tips and tricks to no avail. I used the cmd prompt to look at the C drive and the 1 TerraByte HDD was completely full. I did a disk clean and unfortunately I think it must have also wiped the D drive so Win Re is now completely gone. The HDD must have filled during my last OS upgrade. I am comfortable re-installing Win 10 off USB. Where can I find my Win 10 product key? The information is not in the Q code sticker on the notebook.
Starting with Windows 8, Microsoft has required that all PC manufacturers put the Windows OEM product keys in the PC's BIOS.
You do not need to have or know the product key to reinstall W10.
Your notebook should also be supported by the HP cloud recovery tool which you can use to create a bootable USB recovery drive that will reinstall W10, the drivers and the software that originally came with your notebook.
Here is an info link for how to use that utility...
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