How can I fix an Install Failed error while installing Lion?

I downloaded the new OS X Lion from the App store. I am running the latest Snow Leopard on my 2010 15" Macbook Pro. During the download, it somehow stopped while I was away from the keyboard. When I returned, I resumed it again, and after download completion, began to install it.

When it rebooted, it began to install Lion, and when it was at the 33 minute mark, it failed.

See pictures below:

I got the error message:

Install Failed

Mac OS X could not be installed on your computer

Mac OS X couldn't be installed, because the disk Macintosh HD is damaged and can't be repaired.

I read somewhere that I should put in the original install DVD, and run the Disk Utility to try to verify and repair.

I put the disc in, booted it, and clicked through past the language selection, but made sure to wait for the top menu bar to appear to get to Disk Utility. I clicked on Verify Disk, and got this error message after it ran:

Invalid node structure

The volume Macintosh HD could not be verified completely.

Error: This disk needs to be repaired. Click Repair Disk.

After clicking Repair Disk, I got this error message:

Disk Utility stopped repairing "Macintosh HD"

Disk Utility can't repair this disk. Back up as many of your files as possible, reformat the disk, and restore your backed up files.

I'm also running Bootcamp, with Windows 7 installed in it's own partition. I don't know if that has anything to do with why I'm getting these error messages or not, or if that's why it thinks the hard drive is damaged.

How do I fix this?

I am unable to get back into Snow Leopard. Every restart leads back into the Lion install, which results in these errors. I think many others are having this issue as well.

I do have my files backed up (not in Time Machine, but manually on an external USB drive). I don't mind wiping everything (including Bootcamp), but I rather that be a last resort.

Reference:

• Install Failed - Disk is damaged on Apple Discussions site.

I ended up bringing my Macbook Pro into the Apple store. The genius there attached the store's OS X Snow Leopard via USB, and booted from it, and ran the Repair Disk, which gave the same error of an invalid node structure. Since it was still under Apple Care, I got my hard drive replaced and was able to keep the old one.

With the new hard drive, it had Snow Leopard on it, and I simply upgraded it to Lion without a problem. I was able to attach the old hard drive via USB, and restore all my files.

Thanks everyone for their help. +1 to everyone.

An erase may fix the node structure. Also tools like Drive Genius or Disk warrior - but if you have a backup, it will likely be much faster to just erase the drive.

That way you'll know it's OK or if it can't erase itself properly from the boot drive - you can swap out the HD (or whatever repair is appropriate) and then proceed.

Until you're ready to bring a tool other than Disk Utility to bear or try an erase - you won't be able to proceed. :-(

If it erases fine (without error) - you should be good to go. Just bad luck with the directory structure. If the drive is failing, you'll keep getting those sort of errors that are not recoverable - even during or after an erase attempt.

To just get back to Snow Leopard you shouldn't need to do any of this hocus pocus -

While in the Lion Installer ("Install Mac OS X" window) do q of select "Mac OS X Installer">quit from the hidden menubar at the top of the screen - You will be presented with a dialogue "Are you sure you want to quite?" select "Choose Startup Disk..." - select your Snow Leopard disk and click "Restart..."