Hard Disk - (3F0)

[BMWcsBob]

All in one is on a power strip. 

Had power outage. 

All in one  shut down. 

On power up got blue screen with boot device not found 

Hard disk - (3F0)

Ran memory test.

Ran hard drive quick check. 

No hard drive installed. 

Now what?

[TheOldMan]

That typically means the hard drive has failed.  Since you have already run the diagnostics and it says no hard drive installed, that is a good indication the drive has failed also.

The drive will need to be replaced.  The spec page indicates the drive to be 1TB SATA 7200 RPM drive - quite common.  Usually about $50.  Then install Windows 10.  You can use the HP Cloud Recovery tool or make your Windows 10 install media.

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. Use this new media to install Windows 10.
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.