Dual Boot error: The selected boot device failed. Press <Enter> to continue.

[mouri11]

I have Ubuntu Mate 20.04 installed alongside Windows 8.1.  I used to boot into Ubuntu by pressing F9 and accessing the boot menu. Until today, it was working just fine. However, when I tried to boot into Ubuntu, I am facing the above issue. I couldn't find a suitable solution online. I tried disabling Secure Boot, but didn't help. The BIOS boot menu shows the following three options:

1. OS boot manager (boots into Windows)

2. ubuntu (TOSHIBA xxxxxxx) (boots into grub)

3. Boot from EFI file.

If I choose the third option, it shows the ubuntu entry, however it does not load into it. I have an old backup of my Ubuntu files, but I'd rather not reinstall it, and lose everything. I think the boot file has somehow got corrupted.

Please help. Thanks. 

Edit:

I ran sfc /scannow and found some corruption errors. Attaching the log here. CBS.log

[WAWood]

@mouri11 

We're not HP Tech Support, so we don't do error log debugging.

I'm sorry, but HP only warranties their PCs for usage with the OS that comes preinstalled.

IF you replace that with a Linux distro, or add a Linux distro, then you assume full responsibility for maintaining that -- including solving any problems with booting the other OS and/or installing the other OS.

Modern PCs with UEFI, instead of the older BIOS, are especially difficult to install because you have to go into the UEFI settings and make several changes before you can even boot from a USB stick -- and we are unable to assist in that work.

Your best bet for support now is to contact the support forum of the distro you are using.

Since you are using Ubuntu, go here: https://ubuntuforums.org/

Good Luck

[mouri11 · Accepted solution]

There were some files which got corrupted in the boot partition of Ubuntu. All I did was create a live USB having boot-repair, install to the USB stick using F9, and let it do its work. More info on boot-repair . Thanks all.