I wrote a part of a bootable image to the hard drive with the dd command and now i can't finish installing a linux without getting a grub fatal error...how can i restore my hard drive?

We need a lot more information here. To start with, why did you only write part of the bootable image to the drive? What happened that you had to stop before the image was fully written? Is there a reason you can't simply redo the operation to competition?

What is the image of? Did you accidentally write it to the wrong part of the drive?

You probably cannot restore it, based on how you describe the problem. It's more likely that you will need to reformat it.

Try booting the computer to a Live CD such as Knoppix and seeing whether you can mount the partitions on your hard drive and take a look at them. This should give you a idea of the extent of the damage and also allow you to make copies of any crucial data files that are still readable.

Knoppix is not specifically designed for data recovery, though it can be used for that.

Here is a list of data recovery tools that I found.

I've tried to reinstall and completely clear out the drive with new partitions but it wont let me finish installing...gives me a fatal grub error...when i boot from a live kubuntu usb i can see it like created an embedded mandriva iso partition that doesn't show up in the installer when it gets to the drive specs...kno of any app that would let me locate that partition and delete that partition?

I initially didn't see ur post...i was trying to write a bootable mandriva iso to a flash drive and accidently wrote it to the hard drive...while writing it started shutting down the pc and i powered it off...hence the partially written...and my other reply should give u some more info as to my prob

If Grub is installed to the MBR, you may have to format the MBR and reinstall Grub.

This article explains how to do that with the dd command. I know it works, I've done it.

http://linuxgazette.net/issue63/okopnik.html

Proofread the command carefully before pushing enter. Once it's done, it cannot be undone.

I'm sorry...i forgot to close the thread...anyway...i did manage to fix it...first i unmounted the embedded mandriva partition...deleted the partitions...formated the partition ntfs...made a txt file on it...then it let me install kubuntu...i think mandriva was linked to the ext4 partition in the mbr and by formatting it ntfs it couldn't itself or something...i really don't know but that worked...