Ubuntu – How to use a 4GB USB flash drive to install Ubuntu 12.10

I installed Windows 8 alongside Ubuntu with no dual-boot problems. In your case I would try this:

1. Boot into Live Ubuntu, using a USB pen or CD.
2. Open a terminal and type:
3. sudo add-apt-repository ppa:yannubuntu/boot-repair && sudo apt-get update && sudo apt-get install -y boot-repair && boot-repair
4. If you are not secure of what you are doing, just press Recommended repair button.
5. If you know what you are doing click advanced options and configure the Grub installation as you will.

If you modified the NTFS partitions because your Ubuntu install was running out of space, then note that this would have had no beneficial effect. Since Wubi uses a fixed virtual disk. Instead refer to https://help.ubuntu.com/community/ResizeWubiDisk or https://help.ubuntu.com/community/ResizeandDuplicateWubiDisk

It seems that in modifying your NTFS partitions, it generated new UUIDS. As you have an entry in your /etc/fstab that tries to mount /host on the partition with UUID 7802EDF027EA234. And your grub.cfg refers to that same partition.

So that's causing the error because there is no such partition. It would be the same error if you had copied the Wubi install from another computer.

But try this. When you see the grub menu (if it doesn't show, hold down Shift to make it appear), then press E to edit the entry and change it to look like this:

menuentry 'Ubuntu, with Linux 3.5.0-25-generic' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-3.5.0-25-generic-advanced-d9f4b9a9-784c-4bf7-b1ac-e7f43a731ef7' {
    gfxmode $linux_gfx_mode
    insmod gzio
    insmod ntfs
    set root='hd0,msdos1'
    loopback loop0 /ubuntu/disks/root.disk
    set root=(loop0)
    echo    'Loading Linux 3.5.0-25-generic ...'
    linux   /boot/vmlinuz-3.5.0-25-generic root=/dev/sda1 loop=/ubuntu/disks/root.disk ro   quiet splash $vt_handoff
    echo    'Loading initial ramdisk ...'
    initrd  /boot/initrd.img-3.5.0-25-generic

So, in summary, you deleted a bunch of lines and changed the line starting linux... to refer to the root=/dev/sda1. Now press Ctrl+X to boot.

After booting, drop to a terminal Ctrl+Alt+Tand run sudo update-grub.

Also, for a Wubi install it's completely unnecessary to mount /host as it's done automatically for you at boot time. So delete that line from the /etc/fstab.