I am a beginner and want to try Ubuntu for the first time.

I have the Lenovo Y700 laptop with UEFI (access to UEFI with "NOVO" button)

I want to install Ubuntu on my external HD (WD My Passport 1TB), without influencing the system boot, UEFI and the internal drive (with Win10 on it).

Now, I know that many users had problem after installing Ubuntu on an external HD on a PC with pre-installed windows in EFI mode.

As I understand, to prevent changes in the UEFI, one of the solutions is to install Ubuntu in Legancy mode. I don't mind to change between Legancy mode and the UEFI anytime i need to use either Win10 or Ubuntu.

So, i used Rufus with the image ubuntu-16.10-desktop-amd64.iso to make a bootable Ubuntu installation USB Stick first. I set it for MBR partition scheme for BIOS or UEFI in FAT32 file system.

Then I boot Ubuntu in Legancy mode, connected to the network and start the installation progress.

  1. I've chosen the boot loader to be installed in dev/sdd (my dedicated external drive).
  2. I created two partitions on my sdd drive: swap partition and main ext4 partition. there is another big NTFS partition that i don't want to use for Ubuntu.

When i press Install Now, instead the regular "write the changes to disks?" window to confirm the changes and start the installation, i get the following window:

go back to the menu and correct this problem?

The partition table format in use on your disks normally requires you to create a separate partition for boot loader code. This partition should be marked for use as “Reserved BIOS boot area” and should be at least 1 MB in size. Note that this is not the same as a partition mounted on /boot. If you do not go back to the partitioning menu and correct this error, bootloader installation may fail later, although it may still be possible to install the boot loader to a partition.

there are two options:

  1. Go Back - to create the "Reserved BIOS boot area" partition.
  2. Continue

Which of these i need to choose, in order to not make any changes to my internal drive, to the UEFI settings and to not harm the WIN10 boot?


  • You must create a BIOS Boot Partition that's used to store part of GRUB. – Rod Smith Oct 27 '16 at 13:48
  • rod smith, using Gparted? so i need to create unformatted partition (BIOS Boot Partition) within the sdd (external drive) at 1mb? how to menage flags? "legancy_boot"? it will not harm the UEFI and win10 boot? – gentlegiant Oct 27 '16 at 19:51

Your Answer

By clicking "Post Your Answer", you acknowledge that you have read our updated terms of service, privacy policy and cookie policy, and that your continued use of the website is subject to these policies.

Browse other questions tagged or ask your own question.