My computer does not have a working CD rom drive, so I had booted from USB (used UNetbootin to make the USB) to install Ubuntu initially. I had Ubuntu working on my laptop (Gateway 7330gz), started messing around with it, and decided I wanted to start fresh again. So after searching the web for a how-to on reinstalling I thought I understood that I should hide or delete the partition that was selected to boot from. Now, after deleting this partition, when I boot this is all that comes up:

GRUB loading.
error: no such partition
grub rescue>

My CD rom drive does not work, and for some reason it won't read from the USB anymore, so I can't boot from anything. The only commands for the rescue mode that I've found to work are ls and set but they are the only two I know so far. I'm hoping there's a way to manually tell it to boot from the usb from this rescue mode. When I type in ls i get:

(hd0) (hd0,5)

and when the usb is plugged in it adds (hd1) (hd1,1)

When I type in set i get:

prefix=(hd0,1)/boot/grub
root=hd0,1

Pllllleeeeeeaaaaaseeeeeeee help

Are you dual booting?

Why can't you change your BIOS settings to boot from USB and do a fresh re-install? Grub will not prevent you from doing so.

No, not dual booting. I had installed Ubuntu the first time off USB and had it clean everything else out. The BIOS settings can be changed, but only to ID HDD, FDD, and CD/ROM. I'm guessing FDD is the USB one, and it is active. I've read that if it is setup to boot from a Linux type partition than that will prevent any future booting from CD or USB. I had OpenSUSE on it before I put on Ubuntu, and the only way I could make Ubuntu install was to mess with the fdisk settings in the terminal and I somehow made it so there was no bootstrap....idk

No, whatever you read was false. You can tell it to boot from the USB and then go back later and change it to boot from the hard drive again. FDD is the floppy drive, though. However you got it to boot from the USB the first time you should be able to do it again.

I don't know his/her hardware. My old box doesn't have at all a BIOS setting to boot from USB (it is that old...). My guess is to look at the software (Unetbootin?) or google in that direction.

If you have access to a second computer you can create a boot floppy with GRUB and use that to fire up your installation, i.e. you have to (re)-create the /boot partition you deleted and (re)-install grub there.

And no, you don't have to hide or delete your boot partition to re-install, just select install from the start menu early in the installation process.

I have installed ubuntu ultimate in my pc and windows 7 .when i start my computer it reads :"error no such partition. Grub rescue.how can i start my computer?

George kipkogei cheboror

Start a new thread. This one is eighteen months old and your problem is different than the OP.
First, provide informatin on the hardware you have.
If you have Ubuntu and windows 7, in which order did you install them?
When you installed Ubuntu, where did you install the Grub bootloader? master boot record? partition?
The error "no such partition" probably means the bootloader is pointing to the wrong partition and not the one Ubuntu is on.
Use the installation CD of Ubuntu, open a terminal and run the command: sudo fdisk -l(lower case Letter L in the command) and post that partition information here.

Also, if you know how to mount the Ubuntu partition on the hard drive, do that and post the contents of the /boot/grub/grub.cfg file. If you don't know how, post back so someone can explain to you.