I was trying to install ubuntu 14. onto a usb stick. It booted fine from the USB and I went through the process for a while until I got to the partitioning bit, I was thinking maybe the install was in memory because it gave me the option of partitioning the USB I had booted off (and the install was on), didn't think it would work but I clicked 'YES' anyway and after a second it came back and said it wasn't possible. So I escaped and exited the install through the menu, and since then I can't boot from any USB devices.
The only change I noticed was that originally the USB device was listed in the BIOS separately from the HDD under 'Boot Device Priority' like so:
- USB Flash Drive
- HDD0 blah
- Network Boot
but now it just shows up with one of either HDD or USB, and the second menu on the boot screen in the BIOS controls which will boot (called 'Hard Disk Drives').
Not sure that is relevant, but I thought it was weird.
What ever I try, different orders, diff 'USB Boot Priority High/Low' etc nothing works. If I disable everything except the USB drive it still boots off the HDD.
If I remove the HDD, I then get the grub error:
grub error no such device entering recovery mode
Best Answer
Clicking YES to that option has FUBAR'd the USB stick's bootability.
You will need to repeat the steps you took to create a bootable USB.
During start-up, the BIOS detects any bootable drives that are curently present, and shows those drives in the boot menu. Once your USB is bootable, it will show up again in the boot menu.