VirtualBox Ubuntu guest from real partition image boots into emergency mode, can't get to login screen

I've got a dual boot system on my disk:

• Windows 10 64-bit: main OS
• Ubuntu 64-bit: secondary OS

I installed VirtualBox; I'm trying to use my real Linux partition as a Virtual Machine using Windows as the host. I've used the methods described here.

Grub loads from the bootloader and allows me to select Ubuntu. I go through the loading screen, but never make it to the login page. Instead, it puts me into emergency mode on SystemD:

Looking into the logs, it seems that the VM is running a read-only system. How do I make the VM run a Read-write file system?

• Ubuntu works completely fine when booted on its own
• I have a CPU that supports 64-bit
• I have EFI booting on my computer and on VirtualBox, because they literally demand it
• I have virtualization on in BIOS, for sure (I've quadruple checked)

2 Answers

Only your host OS, Windows 10, requires EFI. You need to disable EFI on the VM. Afterwards treat the virtual machine as if EFI didn't exist, and read How to install Ubuntu on VirtualBox?.

I have exacly same problem I followed these instructions and I end up with same error. Solution which allow me to complete booting process was to

edit sudo nano /etc/fstab

and comment line with /boot/efi (by using #)