Grub installation failed

I'm installing Ubuntu Gnome 14.04 from a bootable usb drive. When it gets most way through, a window pops up that says "Grub installation failed. The 'grub-efi-amd64-signed' package failed to install into /target/.
Without the GRUB boot loader, the installed system will not boot." So I would assume something is wrong with the usb. I'm currently typing this while running on the bootable usb drive, so my question is can I re-download the ISO, and then install it on my computers hard drive from the bootable usb drive? I would just make another bootable usb drive, but I don't have another usb drive. Any advice is appreciated, thanks.

So from what I understand you want to install the OS whilst running on the live USB? If you think it's a problem with the ISO file itself, you can check the md5sum to see if it matches. You can usually find the md5sum on the download page. If it doesn't, something must have happened during the download process. If it does, the ISO file is good, but something probably happened during the writing process. If that's the case you have two things you can try that I know of: You can attempt to mount the ISO file within the live session and see if it will let you run the installer, or you can go to another PC and use a tool like UniversalUSBInstaller (which I have used to write a lot of ISO files and never once had a problem with) to re-write the ISO image to the USB. If it still doesn't work, I'm not sure what else to do. There is probably some one who is more adept in the ways of Linux that could give you a better answer than me. I hope this helps.

Do you have an EFI partition?

I checked the md5sum, and it didn't match up. I just went without my laptop for a night and then used my friends laptop and pendrivelinux to make a new flash drive. As for the efi partition, yes I do, why do you ask?

Try Super Grub disk.


Ok, since the md5sum didn't match, then you need the re-download the ISO (make sure the md5sum matches), and then re-write it to your USB.