Hello, I'm facing some problems when I try to install Ubuntu with Windows (Dual Boot) and when I try to install just Ubuntu. Ubuntu-Windows problem: At first, I always install Windows 10 and afterwards, I run the Ubuntu Live USB in order to get Ubuntu with GRUB installed for choosing which OS I want to run at a later time. Once it is installed, Ubuntu asks me to restart the PC and unplug the USB. When the restart scenario comes, it always starts with Windows 10 and everytime I try to install GRUB with a Rescue USB, it doesn't work. Problems when I want to install just Ubuntu When I faced the dual-boot issue, I thought about installing Ubuntu first and afterwards create a partition for Windows and create GRUB at a later time. When Ubuntu asks me to restart after the installation process, I can see a sentence that dissapears in a second that says something about "Boot0001 with label 'ubuntu' for file "\EFI\ubuntu\shimx64.efi" and it enters into a reboot loop which can only be fixed if I reinstall Windows. My Mini PC is set up for run at Legacy mode with Secure Boot disabled and I can't figure out what it's the problem with Ubuntu. Is there something that I can do in order to fix this? Thank you very much in advance.