I have Installed Ubuntu 12.04 which is working so so perfectly and I tried to upgrade from 12.04 to 12.10. and at the middle of the installation, a notification occurred as installation failed and then it restarted then, it showed GRUB failed to boot at startup and nothing will show up. So, I tried to install GRUB through the terminal using th Live CD Boot. Eventually nothing worked out.
Then I installed V12.10 again using a Boot CD that I created. Yet again the same problem occurred with a notification at the middle of the installation like I/O failed to install or something. Then it killed the process and restarted the computer producing the same GRUB failed to Boot. Being Suspicious about the CD, I checked the checksum of the .iso file and it proved to be ok.
Then I decided to try the USB boot. So, I created the Boot USB and I tried to install it again, only to find the same problem yet again and get a Boot failure.
So Pity Me. Had tried about 8 to 11 times to install it. So now, I doubt the whole OS, UBUNTU V.12.10. Any experts on this.
PS: I tried every bit of command I could find on the net. Nothing Helped. Is this a Problem with Canonical. Cos, even the upgrade on the OS fails to install. This has never happened with my upgrade from 11.10 to 12.04.