I have the usual problem: Ubuntu won't boot. I will explain step by step everything I did as I am not sure what stuff is relevant and which is not:
- I started with fresh install of Windows 10 during which I learned that my netbook has UEFI and SecureBoot and these work differently than I used to (i.e. instead of pressing F12 or similar keys early during computer startup I have to go through convoluted Windows menus and reboot in some special mode)
- Then I have prepared USB stick by simply copying files and setting the boot flag using GParted (because I have read somewhere that this is sufficient for UEFI systems)
- I have managed to boot into Ubuntu live session from USB and run the installation. The process was rather smooth with only one quirk: turned out that Windows installer weirdly partitioned my hard drive with some Windows-specific stuff at the beginning of the hard drive and the main windows partition at the end, leaving free space I wanted use for Ubuntu in the middle. However, the Ubuntu installer didn't complain about anything and was happy to install system there (I am not sure if this is normal or not).
- After that the installer told me that everything is fine and it will reboot now. Then the netbook shut down and booted back to Windows 10.
- As pointed in similar question, I have tired the
boot-repair
tool (using guide provided by Ubuntu Wiki). However, the recommended repair option failed with some message about Secure Boot being enabled. - In BIOS I switched startup mode from UEFI to Legacy and tried the
boot-repair
again - now it complained about being Legacy instead of EFI. - I went to BIOS again and changed startup mode back to UEFI but I have set a supervisor password and disabled Secure Boot.
- I tried
boot-repair
tool yet another time - now it succeeded and told me to reboot (and gave my some tips what to do if it still doesn't work). After reboot, the computer again started to Windows 10.
boot-repair
told my that in such a case I should use following line in Windows console:bcdedit /set {bootmgr} path \EFI\ubuntu\shimx64.efi
The command succeeded (when run in administrator mode) and after reboot the computer greeted me with No Bootable Device message so now I am not even able to boot into Windows.
After that I have run out of options. boot-repair
yield me this report and told me to take it to some forum.