How To fix a Ubuntu system if it won't Boot
You'd probably see a screen similar to this when your Ubuntu system fails to boot. The sad part is that Ubuntu doesn't offer the Safe mode or Automatic repair that Microsoft does in it's Windows. The only thing it offers is a full recovery of your files and programs and also a reinstall option. If you can’t boot anything — not even a USB drive or CD — you may need to configure the boot order in your BIOS . If this doesn’t help, there are chances of a hardware problem with your computer. Check if you can Access the GRUB Boot Loader The first thing to check is whether you can access the GRUB2 boot loader. Boot your computer while holding the Shift key. If you see a menu with a list of operating systems appear, you’ve accessed the GRUB boot loader. If you don’t see a menu with a list of boot options, the GRUB boot loader may have been overwritten, preventing Ubuntu from booting. This can happen if you install Windows on a drive after installing Ubuntu ...