No bootable disk, sudden reboot

[arnnny]

Hi, I've got 2 Probooks which have this same problem. They suddenly reboot and say - no bootable disc - insert disc and press any key... They do this rarely, but it's kinda problem. Reset the BIOS to factory settings or try to update the BIOS? Thank you.

EDIT

I've updated the BIOS to version from November 2016 and tested HDD with HDTune, which showed 100% health and 100% in surface test. Will see if it works.

[WAWood]

It's unlikely that the BIOS has anything to do with this problem.  More likely, the Windows filesystems are getting corrupted and that is causing boot problems.

you will need access to a working PC for this step in order to create the media needed to repair your PC boot loader.

Once you have that, please download and create Win10 install media from this link: http://windows.microsoft.com/en-us/windows-10/media-creation-tool-install?ocid=ms_wol_win10

Yes ... I know that is for Win10, but it uses the same generation boot loader as Win8x, so it can be used to do boot loader repairs for Win8x as well as for Win10.

Boot from the media you created, and follow the directions in this link: http://www.windowswally.com/how-to-fix-error-code-0xc0000185/

You will probably have to run Startup Repair three times for it to fix all the boot loader problems.

When done, your PC should boot OK. If it does not, you have a more serious problem.

Good Luck

[arnnny]

Actually, PC boots fine, but 1/10 times the message shows up.

EDIT

I have created installation media, but not with this media creator. Got Home and Pro Clean ISO of Windows 10.

[arnnny]

I've done chkdsk /f /r . For now - no problems.