Disk boot failure, insert system disk error afte hibernation

[Ed-B24]

So this message was from 2011 and is now archived, but it exactly is my problem.  There was no solution that worked for this person:

Disk Boot Failure, Insert System Disk and Press Enter

 ‎01-22-2011 02:47 PM

I have been experiencing an intermittent disk boot failure for the last few months on my HP Pavilion Slimline PC. At first, it would occur once every week or two, typically when the computer would boot up after being in hibernation. After turning off the computer and turning it back on, everything worked normally. Within the last month, the failure began occurring with more regularity.

This week, I started receiving the error every time the computer would boot from hibernation. I went into the BIOS and saw that the system was not recognizing the hard drive. I tried changing the boot priority to boot from the HDD first, but to no avail. Today, the system worked as usual until I performed a restart, and it has yet to work again. Additionally, the performance has taken a nose dive over the last week (slow processing, programs not responding, etc.).

[Prométhée]

Hello
I don't know which posts you are referring to, as there are a lot of them.
But if nothing to work, still I don't know what was suggested, and done..
but what is likely, if nothing has to be done, is that the hard disk may be defective
So, before it's too late, back up your personal data if you haven't already.
Have you done the full tests?

HP PCs - Testing for Hardware Failures | HP® Customer Support