Boot device not found

[Tom1980]

My son was using his laptop and all of a sudden he gets Boot Device Not found error message.  I need some help resolving this

[TheOldMan]

That typically is the result of a failed hard drive. 

To run the Diagnostics routine, Start tapping the Esc key BEFORE starting the PC and then press the start button.
Keep tapping the Esc key until a popup menu shows. Then pick Diagnostics from that popup menu, F2.
Report back with the results.

[Tom1980]

I tried the short boot and it passed.  I am in the process of checking the long boot. It still has 3.5 hours left.  

[Tom1980]

Ok, the two scans both passed but still can not load the device.  Still getting boot device not found.  Hard disk 3F0.

[TheOldMan]

That is good news. 

There could be several reason that message appears.

1) the boot loader has been corrupted

2) there is a media in a card reader - remove and try again

3) the is media in a DVD/CD drive - remove and try again

4) the is a flash drive in a USB port - remove and try again

5) last resort - disconnect anything but the keyboard and mouse - being this a laptop that should be easy to accomplish

Since the model number and Windows is not posted, lets assume at least Windows 10

Boot the laptop to the Windows installation disk or USB.  Attempt the repair function first.  If that fails, then reinstall Windows

If you need the install media for Windows 10, you can make it from this Microsoft download

https://www.microsoft.com/en-us/software-download/windows10

With a working PC, scroll down to the "Using the tool to create installation media"
and then follow the directions. You can make either the DVD or USB.
When the install asks for the product key, click the I don't have a product key option to continue,
then the install will continue It will be activated once it connects to the internet, as it uses a digital key.

[Tom1980]

I ended up buying a new hard drive from bestbuy. A bookable USB did not work.

[TheOldMan]

Yes, Windows is made to not be a working OS from a USB flash drive or a USB hard drive, also know as Live OS.  That is a constraint built into Windows.