Installing virtual machine with KVM failed on "Load installer components from CD"

Solution 1:

The main problem is that the virtual disk you have created is not formatted, it is just a raw disk without a partition table. Another issue is that you selected the format qcow2 and created an .img file. You have to execute this command : qemu-img create -f qcow2 ubuntu.qcow2 20G.

Download the latest stable version of GParted Live | Direct download link -> GParted 0.26.1-1

Insert the ISO file and the virtual disk, boot from the GParted ISO file, create a new partition table, new partitions and and format them. Here is a presentation on how to prepare a disk.
This is an advanced advice, creating the partition table and format it with ext4 is sufficient.

kvm -hda ubuntu.qcow2 -cdrom gparted-live-0.26.1-1-amd64.iso -boot d -enable-kvm  

After the operation is finished close (poweroff) GParted Live to shutdown the virtual machine. Now insert the Ubuntu Server 14.04 installation media and start the installation of the system.

kvm -hda ubuntu.qcow2 -cdrom ubuntu-14.04-server-amd64.iso -boot d -enable-kvm  

Note : These are the basic commands - choose the paths where the files are located and add additional boot options that fit your needs, for instance the amount of memory (-m 8192).