I get the following error during boot up:

Verifying DMI Pool Data.............
GRUB Loading stage 1.5.

GRUB loading, please wait...
Error 21

Any ideas how to resolve this? Thanks in advance.

Alex

Depends on distro? If it was a live install you can fix fairly easy, if not get a live cd:

Boot from live cd
login as root (or su)
type grub in a term
root /dev/sda? (? being where your controlling distro was)
setup sd? (or wherever you want the mbr loaded)
quit

DONE!

I'm using Ubuntu 8.04 and have the live CD. What would the code be for that distro? Thanks.

Alex

Error 21: Selected disk does not Exist. More detailed information would be needed before you could get a definitive answer. I had this error on my computer and it was just a loose connection from the power supply to the first hard drive. What were you doing immediately prior to getting this error, had you installed any new software, hardware, etc.?

You may not need to re-install Grub. If you do
su (hit enter)
(enter passwd)
you will get the grub prompt
grub> root (hd0,1)##this command shows boot partition for your system as first drive,2n partition
setup (hd0)##this writes Grub to mbr of first drive
quit

That is not likely your setup so you need to make changes. If you are not sure how, post again with results of "fdisk -l" command. Also post any changes you may have made recently, if any. This would probably be the way to go rather than re-installing grub.