Ubuntu GRUB Error 21

[vicMasters]

I tried dual booting ubuntu on my vista ultimate machine and the installation failed. Now when I attempt to boot I get the message "GRUB Loading, please wait... " then on the next line it says "Error 21". I've looked up a few solutions to this problem but nothing that is similar to my case can be found. I can't login to vista at all. My question is does anyone know how to recover my vista partition without having to re-install? You see, I have a programming assignment on it that is due tomorrow at midnight:mad: .

So far, I have loaded ubuntu using the install cd but never fully installing and going into the partition editor, then deleting the 15g partition that ubuntu was installed on. This did not work. Then I tried re-combining the space that I allocated for the Linux installation to the partition that windows is on. This failed also. I still get the GRUB loading error. Can anyone help me?

[uOpt]

Boot from the CD with
"linux rescue"
at the boot prompt.

Do a "grub-install /dev/hda" or whereever your grub lives.

Did you originally install grub into a partition or into the MBR?

[vicMasters]

I installed it into the partition by selecting install from the linux desktop, then when prompted for installation destination I chose install on continuous free space. Doing so was supposed to automatically install unbuntu onto the new partition if I'm not mistaken.

[eden40000]

I had the same problem last night. Booting from your Vista dvd and using the troubleshoot startup option - you rapidly see that vista doesnt think it has a problem - yet wont start or show a boot manager.

I pretended like I was going to install vista on a new partition, let it get to the first re-start, and was able to lightning finger over to my old vista install before the new vista install resumed (when it pops up a vista boot manager screen for like 2 seconds.)

From there I used easy BCD to re-write the boot manager.

Pain in the arse. Really put a damper on my mood - and that pretty much put the kibosh on me installing Ubuntu for now. The live cd worked at least...

[uOpt]

There is a difference between installing Linux into a partition and installing grub into a partition.

Of course you always install Linux into a partition. But with Grub you can choose to either install into your Linux partition or into the MBR. Installing into the MBR does not disable multi-boot and other operating systems in non-Linux partitions.

I think that the above error means the following happened:
- installed grub "guts" into Linux partition
- then reformatted Linux partition
- so that the Grub guts are now gone and the top-level loader can't find them

You should install grub into the MBR (hda, not hda2 or the like) to avoid this problem until you are experienced enough to deal with nonsense like this.

Having said that, the partition editor and boot install selector really isn't the bright side of Ubuntu and Grub is a POS. Grub is a major reason why I rate FreeBSD much higher than Linux.