How to solve grub installation failed
sudo apt-get install lightdm dpkg-reconfigure lightdm. 3. Reboot the system. Conclusion. The above methods are the most common ways to fix login loop in Ubuntu. Sometimes re-installing graphics card driver or updating it to the latest version or rolling back to the previous version also helps to solve this looping problem.The error: grub-efi-amd64-signed failed to install into /target/. I have tried: 1- Skipping third-party applications and updates. 2- Creating my own partitions that I have seen from the videos. 3- Downloading the updates and third-party applications. 4- Restarting.