I installed Ubuntu Mate 10.04.3 as a dual boot OS in my windows 10 Thinkpad T470s using a USB. I turned off the secure boot option to install Ubuntu from the USB. After installation, when I tried to restart, I had to enable the secure boot option. Now when I try to login, I don't get the option to select Windows or Ubuntu, it goes directly to Windows. How can I get that screen where I can choose OS?
1 Answer
If I remember right, you have to have Secure Boot disabled for linux, generally speaking. You should still be able to boot to Windows with Secure Boot turned off though. Try turning it off, powering down fully, then back up. Does it take you to the boot menu then? Is there an entry to boot both partitions?
Hopefully the installer setup the bootsector to boot to either partition from the menu. It is optional for advanced uses, but usually you want to set it up when you install. You may have to create an entry for the Windows side if there isn't one.
If it still doesn't work, check for other options relating to Secure Boot, also boot order. To dual boot, boot to the linux partition first. Then from the boot menu, you should be able to boot to either partition.