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Tried installing windows with a installation CD, i deleted some partitions because it was an unknown partition (which was used by ubuntu) then the installation failed.Now whenever i boot up my laptop i get a unknown file system grub rescue error. What can i do that will fix this error? Is there anything i can do?

I have already tried installing windows xp, but it doesn't identify any hard drives. I've placed a ubuntu installation dvd in the disk drive, but i don't get the prompt to boot from disk. i've also tried going into the grub menu by holding the shift key. It'll say grub loading, followed by unknown file system.

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marked as duplicate by user68186, Radu Rădeanu, Braiam, Eliah Kagan, Kevin Bowen Sep 10 '13 at 4:41

This question was marked as an exact duplicate of an existing question.

I've had my share of problems with partitions and dual booting with my machines too. This topic here ( was always helpful whenever I bumped into the grub rescue screen of death. You could also try using Ubuntu Live CD and running boot-repair (, but the first solution is almost guaranteed to work.

I would recommend installing Windows first and then installing Ubuntu, but last week I had to do the other way around because Ubuntu was messing with Windows boot files (stupid Sony VAIO and its UEFI/Legacy shenanigans), so I don't think this is always the best way to proceed. If you prefer (or have to, like I did) installing Windows later, you'll have to use Ubuntu Live CD and run boot-repair.

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how do you boot from a live cd? whenever i place the cd in the drive and reboot i don't get a promp to boot from drive. but if i place a win 7 or xp installation cd i do get the prompt. how can i make the live cd bootable? – Brian Lopez Sep 9 '13 at 20:13
I have no idea why you can't boot from the live CD, maybe the media got damaged? If you could give us more details of what appears in your screen when you try to boot your machine with and without the live CD, maybe we could help you more specifically. – SkydivingPanda Sep 9 '13 at 21:03
sorry for my late response had to go to school. when i power on my laptop without any disks. I get the Vaio startup screen for just a sec, then afterwords there is a black screen with the error"error: unknown filesystem. grub rescue>" I just inserted a ubuntu disk and it seems to boot up now. i possibly had a corrupt or incomplete download for it. i'm trying to install it now to see what happens. – Brian Lopez Sep 10 '13 at 3:39
okay so it just stayed at the loading splash screen indefinitely as far as i can tell. I did get windows 7 installed though. At first i attempted to install 32 bit windows because i wasn't sure if it was 64 bit capable, then i found my old recovery cd and saw i had it labeled 64 bit. which i then tried to install 64 bit of windows 7 which worked. is there anything special i should do or is this all? – Brian Lopez Sep 10 '13 at 6:02

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