Confirmed and reproduced in Xubuntu 20.10 as well. This issue is _not_ confined to Ubuntu Unity and is also present in an official remix.
Steps taken to try to resolve it: * updated system BIOS (machine is a Lenovo Thinkpad W500; was on 3.18, now on 3.23, latest) -> no change • tried 2 different flavours of 20.10 -> no change • placed a bootable DOS primary partition (C:), set active, tested OK; no change. • installed Windows 7 Enterprise SP1. No UEFI detected, no EFI partition created, no separate system partition needed or used. Ubuntu Unity 20.04 went on this machine without a glitch. openSUSE Leap 15.2 was also fine. The machine does not have UEFI, as far as I can tell. There is no option to boot in legacy or UEFI mode. The only way I have discovered to install 20.10 was to tell it my DOS partition was the EFI System Partition. This worked fine, installed GRUB into /dev/sda and now it boots. However this has rendered my DOS partition unbootable, and now it is mounted at /boot/efi which is not what I want. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1915152 Title: Installation of Ubuntu Unity 20.10 always fails if there is no EFI partition To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubiquity/+bug/1915152/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs