Hey I have a Dell 1526 Inspiron laptop. I installed ubuntu 8.10 on my hard drive in a partition next to a Windows Vista. I decided to download Windows 7 and I wrote it right over the Ubuntu partition. I then installed ubuntu 8.10 on an external hard drive. now when i turn on mhy computer i get a GRUB 21 error unless I connect the hard drive, enter the boot setup, load the external hard drive, and than select vista loader and then select the OS I want to use. I want to be able to turn on my computer and go straight to the vista loader so i can select the os i want to use. what do i do. please HELP!!!!!!

OK, how about booting your Live CD (the Ubuntu install CD), open a terminal (Applications > Accessories > Terminal) and do:
One of the above commands should return your main Ubuntu partition (or /boot partition if you have one) in the form of (hdX,Y) where X and Y are numbers, for example (hd1,0), but use whatever it returns as follows:
That will install Grub to the MBR (Master Boot Record) of your Ubuntu drive. Then to restore a Windows MBR to your Windows drive, try:
Then reboot, set your BIOS to boot the Ubuntu drive, and you should at least get the Grub menu if all goes well. If you are using Intrepid you should be able to boot into Ubuntu, but if you have a previous release your Grub's menu.lst will most likely need some tweaking. Let me know how that goes or if you run into problems.

ummmmmm...........
im really new to the whole linux thing so im not really sure i understand what you said. i hate to ask, but would you mind dumbing this down a little bit?

which is my main partition, the one i reformated or the one i use now?
how would i install a windows MBR?
and i dont know what intrepid is


thanks sooooo much

This would indicate that when you installed Ubuntu 8.10 on the external, you wrote the Grub stage1 bootloader file to the master boot record of the internal drive. The stage1 file is looking for the rest of the bootloader files which are on the external drive. If you don't have the external attached it obviously won't find these files.

What is it that you want to do? Do you want to just boot vista? If so, you can do this:

Boot up from Vista Installation DVD and select Repair Your Computer option (its below Install Icon). Select Windows Vista -- Command Prompt.
Execute this at command prompt:
Code:
bootrec.exe /fixmbr
bootrec.exe /fixboot

Or you can download EasyBCD to edit the vista bootloader and make changes you want including booting Ubuntu. Have never used it myself so I'm not sure how well this works:

If you want to be able to boot vista and Ubuntu using Grub, you will either have to have Ubuntu on the primary internal drive or keep the external plugged in.

Thank you soooooooooooooo much. my computer is back up and running. I think im gonna put ubuntu on my internal hard drive, but im just relieved that everythings working again!!!! Thanks!!!