Same problem here after 2.6.31-19 kernel upgrade. At first I had enduring trouble and great pain booting manually, and I wanted to share the instructions that worked for my system.
The greatest point of confusion for me was that there were no /dev/sd... entries listed via "ls /dev" from the grub command prompt. Despite this, my manual boot succeeded when I used "root=/dev/sda2". in my "linux ..." command. Also, my host (vista) partition was not mounted properly, so I could not "ls /ubuntu". Yet despite that I was able to successfully specify "loop=/ubuntu/disks/root.disk" in my linux command. System details: hardware: lenovo r61i laptop (probably not relevant) host OS: Windows Vista wubi version: ? (probably not relevant) ubuntu version: 9.10 Manual boot instructions: set root=(loop0) linux /boot/vmlinuz-2.6.31-16-generic root=/dev/sda2 loop=/ubuntu/disks/root.disk ro initrd /boot/initrd.img-2.6.31-16-generic boot In Ubuntu after manual root: "sudo update-grub" ("sudo update-grub2" is equivalent?) Notes: You may have to change /dev/sda2 to /dev/sda1. You need to pick the device that corresponds to the windows partition that stores your wubi installation. I think I simply used "ls" from the grub command prompt and got info that suggested I needed to use sda2. (I think the first partition was the windows boot partition). -- After 9.10 grub update can not boot into Wubi install https://bugs.launchpad.net/bugs/477104 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs