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I am trying to install Kubuntu 15.04 from a liveUSB on a hard drive without a prior OS. The machine has a GeForce GTX 980 GPU. The primary problem is that when I boot from the USB and begin the installation process, I eventually see the message Input Not Supported floating across a blank screen. I open a terminal, use the default login parameters, and edit the GRUB config file using the following command:

sudo nano /etc/default/grub

I find the following line and remove the hash (#):


I save the grub config file and try to run the following command:

sudo update-grub

I am met with the following error:

/usr/sbin/grub-probe: error: failed to get canonical path of '/cow'

I have read the articles here about this error, such as Failed to get canonical path of /cow, but I do not understand the nature of mounting here. My hard drive is sda and the usb where ubuntu installer is located is sdb. The lsblk command also shows -sdb1 as a location with a type of part /cdrom.

I have included an image below which elucidates my configuration. Could someone please clarify how I have to mount grub given my configuration? My goal is to get Ubuntu to install and run with this 640x480 resolution so that I can update the drivers and all that once I have finally booted to the desktop. I have used the nomodeset option in the past, but it does not further the installation process. If anyone has any advice on how best to proceed from here to get to that goal, I would be exceptionally grateful.

Screenshot of terminal showing output of 'lsblk' and 'df' commands

marked as duplicate by karel, Fabby, David Foerster, Zanna, ubfan1 Apr 19 '18 at 21:46

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