I'm using HP notebook. Its not even an year old. But it is showing me an error which is "boot device not found error - hard disk (3FO)". I have updated my BIOS version, performed hard drive test(all the test got passed) , then i did complete reset , but i didn't get rid rid of the problem. After that i have reinstalled the OS also. Even after reinstalling the OS, i'm getting the same error again. Please do the needful.
Step 3: Test the hard drive using HP PC Hardware Diagnostics UEFI (In your case, Skip to Step 4)
Step 4: Re-seat the hard drive (here's a generic video that shows how to re-seat the drive: Click here) > 3F0 error represent a hardware malfunction, a reseat should help, if it doesn't or you aren't comfortable, please Contact HP as the next step will not help.
Step 5: Perform an HP System Recovery
If none of the above actions resolved the error condition, back up your personal data and then perform an HP System Recovery on the notebook. See one of the following documents for instructions:
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