unable to boot on Ubuntu after 10.10 update

Normally the upgrade to 10.10 fails (for Wubi installs) - it's in the release notes. There is a workaround: copy the c:\ubuntu\winboot\wubildr file over the c:\wubildr file (or I guess G: on your system). Regarding that, the locked out Admin and the drive switching, I haven't heard of this before. Is it possible you have done something else?

It might help to run the bootinfoscript:
Boot the live CD and download and run bootinfoscript from http://bootinfoscript.sourceforge.net/) and post the results to http://pastebin.ubuntu.com. Then copy the pastebin reference back
here. I'll take a look.

Hello bcbc, thank you for your help. I did copy the c:\ubuntu\winboot\wubildr file over the c:\wubildr file but the "not found wubildr" error message persists and can't boot.
I did run the bootinfoscript.sh as you indicated me, the result is posted on http://pastebin.ubuntu.com./539773/.

You are right I have done something else, I did execute EasyBCD 2.0.2 from Windows before posting on the forum and I probably did something wrong because the hard drive changed from "C:" to "G:" and I guess that's the problem with the windows profile. An answer from another forum say my pc has the Sality.A.Trojan virus but unfortunatly the pc on windows it's unable to execute spywares to scan and clean because there's an error saying something like ".net v4 framework not installed".

Thank you again.

Octavio

That EasyBCD is supposed to allow you to boot a direct partition install of Ubuntu using Windows, rather than Grub in the drive MBR. With Wubi, you don't have a partition install and I doubt EasyBCD would work.

I can't see any problems from the bootinfoscript except that it failed to mount the root.disk. This doesn't always mean that there's a problem. But I think it's likely in this case. From a live CD you can check the root.disk yourself, and try and mount it. If it mounts normally, maybe that will fix Ubuntu.
sudo mkdir /media/win
sudo mount /dev/sda2 /media/win
sudo fsck /media/win/ubuntu/disks/root.disk
sudo mount -o loop /media/win/ubuntu/disks/root.disk /mnt

Note: are you sure you upgraded to 10.10. You can't really mistake this. I ask because copying the wubildr file works to fix the upgrade, but doesn't work on 10.04 - that has also been affected by a grub update in the past couple of weeks. In that case you need to manually edit the grub.cfg file to get it to boot (the problem is described here http://ubuntuforums.org/showpost.php?p=10183394&postcount=87)

Regarding the locked Admin profile and the drive lettering switch - I really have no idea. I actually have had locked profiles on my computer but not sure whether that was Ubuntu related or not. If you think you have a virus, you should be able to tell by running an antivirus program - microsoft has one for free. But a Windows support site would be a good place to get more info. I searched and found this http://support.microsoft.com/kb/223188 (make sure you find the support article for the correct version of windows you are running)