How can I fix the MBR on my hard drive?

Question

I've tried to use fixmbr (from the Windows XP Recovery Console) and pointed it to C:\, but broke it!

Now I have:

D:\Windows - with no ntldr
C:\ - broken inaccessible partition with Grub and ntldr

How can I repair C:\? (I only have Ubuntu)

Answer 1

1. Boot up into the Ubuntu 10 USB stick
2. If it isn't installed already, install GParted.
3. Open up GParted, set the partition with ntldr as bootable.
4. Remove the "bootable" flag from the Linux partition.

That should cause it to boot from the C:\ partition with grub/ntldr. I'd highly suggest testing to make sure that you can still boot after doing this, before reformatting the Linux partition. If it fails, then it's simple to fix.