Bug in the Calamares installer resulting in no installation of the boot loader in the BIOS mode

Dear Lubuntu Team

I’m writing to let you know that there is a serious bug in the Calamares installer with the potential to brick computers due to installations without a boot loader in BIOS+MBR mode.

I thought I’ll update another thread with the same issue, however, considering that thread is locked, I’m creating this one with the resolution.

When we try to install Lubuntu 20.04 LTS using the Calamares installer in the BIOS mode, the installer should by default install the boot loader in a 538MB fat32 partition with the boot flag, however, Calamares doesn’t do that at all.

This results in a bricked device.

Anyone who wants to install Lubuntu 20.04 LTS in the BIOS mode with MBR, needs to go for a manual partitioning, and then creating a MBR partitioning table in the following manner:


I have a 500GB HDD and the above is how it looks like after a successful install.

This bug is not present in the Ubiquity or the Kubuntu installer, because I have installed all the Ubuntu 20.04 LTS flavours except Lubuntu without any issues in the same system applying the same method - automatically partitioning the entire disk in the BIOS+MBR mode.

I also encountered this bug while installing the most recent version of Q4OS.

The Lubuntu team should either use the Ubiquity installer or fix this.

Thank you.

Lubuntu is QA-tested and installs are made on BIOS only boxes, which you can see the final checklist for Lubuntu 21.04 (hirsute hippo) at https://phab.lubuntu.me/w/release-team/testing-checklist/

That is the same checklist that was used in Lubuntu 20.10, Lubuntu 20.04 (original, plus .01, .02 in fact will be amended and used next for Lubuntu 20.04.3), Lubuntu 19.10 and back to Lubuntu 19.04.

We cannot test for hardware we don’t own, but anyone is welcome to come and help us in the QA-testing of releases. See https://phab.lubuntu.me/w/testing/

In fact if you go look, you’ll note QA-testing on impish or what will be Lubuntu 21.10 is already underway.

Have you filed a bug report? If so providing a link to that may reveal some clues.

The help pages for filing bugs can be found at
for Lubuntu & Ubuntu


No, Calamares works correctly. There is no need for a FAT32 partition in BIOS mode. And the correct location for the bootloader in BIOS mode is in the Master Boot Record (MBR) of the disk, not somewhere in a partition (or in the Partition Boot Record PBR).

I doubt, that the device is bricked.

That is not true.

The behaviour of Calamares is not a bug. But the behaviour of Ubiquity is special, because Ubiquity is installing both Grub for EFI- and Grub for BIOS mode. Ubiquity is doing this because they want always a bootable system.

What you are describing is effectively how to install the system in UEFI mode. If you install in BIOS mode, than you have to change the firmware settings to boot in BIOS mode (CSM).
If your firmware is set to boot from UEFI, than you should boot the installer also in UEFI mode.


I regret that I’ve not filed a bug report yet. However, I’ll do that. Thank you for your response.

Except that it doesn’t work in this case.

I assume this is the bug report…

“It doesn’t work” doesn’t help.

  • I don’t see all the necessary steps to reproduce
  • I don’t see the install logs
  • I don’t see any evidence, that no bootloader was installed in the MBR