Fixing Ubuntu Bootable Drive Errors on UEFI Systems

The Unified Extensible Firmware Interface (UEFI) is a specification that defines a software interface between an operating system and platform firmware. It is designed as a replacement for the BIOS (Basic Input/Output System). However, sometimes, booting Ubuntu from a UEFI system can cause errors. This article will guide you through the process of fixing such errors.

Understanding the Errors

The errors “Couldn’t get size: 0x800000000000000e” and “MODSIGN: Couldn’t get UEFI db list” are commonly encountered when attempting to boot Ubuntu from a USB drive on a UEFI system. These errors are typically due to issues with the bootable drive or the UEFI firmware settings.

Preparing the Bootable Drive

Before we start troubleshooting, ensure that your bootable drive is correctly set up. Use a tool like Etcher to burn the Ubuntu ISO file onto your USB drive. Make sure the ISO file is not corrupt by verifying its checksum.

Checking UEFI Settings

The first step in resolving these errors is checking your UEFI settings. Access your system’s UEFI firmware settings by restarting your computer and pressing the appropriate key (often F2, F10, F12, or Del) at the startup screen.

Ensure that Secure Boot is disabled. Secure Boot is a security feature that prevents unauthorized software from running during startup. However, it can sometimes interfere with booting from a USB drive.

Also, check that your system is set to boot from the USB drive. This can usually be set in the Boot Order or Boot Priority settings.

Fixing the Bootable Drive

If the errors persist after checking your UEFI settings, you may need to repair the bootable drive. Boot into a working Linux system and install the gdisk package with the following command:

sudo apt-get install gdisk

The gdisk tool is used to manipulate GUID Partition Table (GPT) partitions, which are used by UEFI systems. The apt-get install command installs this package.

Next, run gdisk on your USB drive with the following command:

sudo gdisk /dev/sdX

Replace X with the letter corresponding to your USB drive. This command opens the gdisk tool for your USB drive.

In the gdisk prompt, input x to enter expert mode, then input n to create a new protective MBR. Finally, input w to write the changes to disk.

This process creates a new Master Boot Record (MBR) on the USB drive, which can resolve issues with booting on UEFI systems.

Conclusion

Fixing Ubuntu bootable drive errors on UEFI systems can be a complex task, but with the right tools and steps, it can be accomplished. Always ensure your bootable drive is correctly set up, and your UEFI settings are configured correctly. If all else fails, repairing the bootable drive’s MBR can often resolve these errors.