Here are some tracks to solve issues when installing Ubuntu:
Make sure Windows FastBoot is disabled and restart in Advanced Mode.
Disable Windows FastBoot & Bios FastBoot (see below).
OR
Access the Bios and change Boot option ONE by ONE <=> choose an option, save, reboot, if your problem persists, come back to default Boot option, choose another option and move on.
- Restart your machine in default mode and keep pushing on F2 or F11 or Suppr. to access the Bios.
- Look for the boot options to disable the Bios FastBoot