I did find drive letters and contents vanish with that disabled. The Linux test ignores such things.
My Dell Vostro 2520 64-bit laptop. Shows the following error on power on.
Internal hard disk drive not found
To resolve this issue, try reseat the drive
No bootable devices -- strike F1 to retry boot, F2 enter setup menu, F5 enter PSA
I ran the F5 Dell internal diagnostic tool. It shows all the rest of the peripherals working correctly except no hard drive status.
The last thing I did with the laptop was to install Virtual Box and install Windows 7 32-bit OS in the virtual guest machine. The next day I got the hard disk not found error. So tried to repair any possible corrupt OS to boot from USB drive but on reboot I get a similar "No bootable devices" error. The laptop should boot from the usb drive or not?
The legacy option is enabled and secure boot is disabled in the BIOS.
What could be the possible cause and fix for the problem.