Kernel panic - not synching

I'm about as big a booster of Ubuntu as you can find without being actually part of the Ubuntu team. But from yesterday till today I've found myself cursing Karmic Koala. The reason: as of yesterday afternoon, after an update, the Wubi install of Ubuntu 9.10 on my HP Mini 2140 just stopped working.

In more gory detail: after going into Grub, I would get the following message:

Kernel-panic - not syncing : VFS : Unable to mount root fs on unknown-block(0,8)

Was I upset? You betcha! I had some important files in that partition that I had not backed up yet.

I did some searching and found the problem documented in Launchpad Bug 477169 and in Ubuntuforums thread 1317397. The problem seems to have first reared its ugly head some three weeks ago and affected quite a number of folks. Apparently it either has something to do with the combination of Wubi, Grub2, and ext4, or with Karmic's update of initscripts_2.87dsf-4ubuntu12_i386.

Much as I appreciate the efforts by the users in the bug report, I found the discussion and the instructions hard to follow. I can't really fault them for it, though; but somehow I wish someone from the Ubuntu team had the ball on this one.

I did manage to retrieve my files. Here's how: after booting into a Ubuntu LiveUSB, I opened a terminal, and mounted the root.disk file found in the /ubuntu/disks directory of Windows. Annoyingly, you'd have to perform a mount within a mound. The commands:

mkdir ~/win
mkdir ~/vdisk
sudo mount /dev/sda1 ~/win
sudo mount ~/win/ubuntu/disks/root.disk ~/vdisk

Your Wubi/Ubuntu file system should now be found in the vdisk directory. You can now copy your files from your home directory to another USB flash drive.

Sadly, not all's well that ends well. I still have some 40 students in my laboratory classes to think of who all have Wubi installations on their computers. What do I do when this problem hits them?