How to Fix: grub error: symbol 'grub_puts_' not found

                One of the main reasons for this error is a corrupted GRUB (GRand Unified Bootloader) configuration file. During the upgrade process, the GRUB configuration file may have been damaged or deleted, leading to the 'symbol 'grub_puts' not found' error.Another possible cause is that the GRUB bootloader was not properly updated during the installation process, resulting in an outdated version of the GRUB configuration file.

            🔧 Proven Troubleshooting Steps

                Reinstalling GRUB from a LiveCD

                    Step 1: Insert the live Ubuntu CD/USB drive and boot from it. Open a terminal and type `sudo grub-install --reinstall /dev/sda` (replace `/dev/sda` with the actual device name of your hard drive). This will reinstall the GRUB bootloader.Step 2: After reinstalling GRUB, type `sudo update-grub` to regenerate the GRUB configuration file. This may take some time depending on the size of your system.



                Manually editing the GRUB configuration file

                    Step 1: Insert the live Ubuntu CD/USB drive and boot from it. Open a terminal and type `sudo nano /boot/grub/grub.cfg` to open the GRUB configuration file in the nano editor.Step 2: Locate the line that starts with `set timeout=10` and delete it. Then, locate the line that starts with `menuentry 'Ubuntu'` and modify it to include your hard drive device name (e.g., `/dev/sda1`). Save and exit the nano editor.


            🎯 Final Words
            To summarize, the 'grub error: symbol 'grub_puts' not found' issue can be resolved by reinstalling GRUB from a liveCD or manually editing the GRUB configuration file. By following these steps, you should be able to regain access to your installed operating systems and boot into Ubuntu successfully.