Dual Boot: Cannot boot into Ubuntu after Windows 10 Creator's Update

Question

Yesterday I installed the Win 10 Creator's update and can no longer see the Ubuntu select OS screen on start-up. I couldn't find the solution anywhere. I'll be grateful if someone can help. Thanks

Answer 1

Just open Ubuntu by using USB stick and run Boot-Repair. You can temporarily install it even if you use USB stick.

From the Ubuntu wiki page on Boot-Repair:

1st option : get a disk including Boot-Repair

The easiest way to use Boot-Repair is to create a disk containing the tool (eg Boot-Repair-Disk, a disk starting Boot-Repair automatically), and boot on it.

Remark : it is recommended to install the ISO on a live-USB (eg via UnetBootin or LiliUSB or Universal USB Installer). Do not burn it on a DVD if your computer has Windows8 pre-installed, or if your boot is in EFI mode.

2nd option : install Boot-Repair in Ubuntu

• either from an Ubuntu live-session (boot your computer on a Ubuntu live-CD or live-USB then choose "Try Ubuntu") or from your installed Ubuntu session (if you can access it)
• connect to the Internet

• open a new Terminal, then type the following commands (press Enter after each line):

  sudo add-apt-repository ppa:yannubuntu/boot-repair
  sudo apt-get update
  sudo apt-get install -y boot-repair && boot-repair
  

Recommended repair

1. launch Boot-Repair from either :
   1. the Dash (the Ubuntu logo at the top-left of the screen)
   2. or by typing 'boot-repair' in a terminal
2. Then click the "Recommended repair" button. When repair is finished, note the URL (paste.ubuntu.com/XXXXX) that appeared on a paper, then reboot and check if you recovered access to your OSs.
3. If the repair did not succeed, indicate the URL to people who help you by email or forum.