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Luke19 09-19-2013 05:56 PM

grub error unknown filesystem - Really need help!
 
Hello.

I have a windows 8 Pc and I installed ubuntu onto it in dual boot, I made a recovery disk and deleted the Ubuntu partition but now I get "grub error unknown filesystem" when booting from the disk and booting normally, Please can someone help me I'm only 13 and if my parents find out they won't be very happy - I have a windows 8 laptop (My Dads) and a Windows 7 Pc (My Mums) I can use to do something with? Please I really need help on how to get Grub working again so I can get my Pc booting again.

- Thanks

yancek 09-19-2013 06:46 PM

Just to clarify things, you first installed Ubuntu and then deleted its partition(s) and now just have windows 8 which you want to keep, is that correct?

What did you make a Recovery Disk of, windows 8?

Quote:

"grub error unknown filesystem" when booting from the disk
That would indicate that when you installed Ubuntu, you installed its bootloader (Grub) to the master boot record of the primary drive. Most of the boot files needed are on the Ubuntu partition - the one you deleted. Since you deleted a partition, the partition numbers changed which is also why you get the error.

Do you have an installation CD/DVD of windows 8? You should be able to boot that and there should be a 'Repair' option on it. You may have a repair option on the Recovery CD that you can use to fix the master boot record.

Take a look at the sites below for some options/details on doing this repair.

http://www.tomshardware.com/forum/45...inux-dual-boot

http://askubuntu.com/questions/14967...ntu-boot-drive

After reading your post again, if you want Grub to work you need a Linux partition on which to install it. Do you want to have Ubuntu or just windows.

Might be a good idea in the future to ask your parents before doing something like this??

haertig 09-19-2013 06:57 PM

For one, you probably won't be able to hide this from your parents. So get ready for any fallout that may occur.

GRUB is a bootloader. It handles the initial stages of booting an operating system. What has happened is that GRUB requires software installed in multiple places on your computer. It overwrites code in your MBR ("Master Boot Record") and also in "Track 0". The code it puts there then jumps to other code GRUB installed in that Ubuntu partition. Now that you've deleted the Ubuntu partition, the GRUB code in your MBR/Track0 has no place to jump to, so booting fails miserably. The MBR and Track 0 are special places on your hard disk. They are not part of the "normal" computer data, except as they relate to the booting process.

This is annoying and scary, but not fatal. Your computer data (the Windows stuff) is intact unless you've done other things that you haven't told us about. As a warning, I would not just jump into repairing this in a hurry so that your parents won't find out. You could destroy everything in your haste. Tell your parents, admit what you've done, go to your room for an hour or whatever punishment they delve out, and then your guys, as a family, can get on with repairing things.

I understand you are in a bit of a panic right now, but if you act in haste, things can, and probably will, get a whole lot worse. It is doubtful that your parents will actually kill you if they find out. More likely, they'll just hack off your arms or something (just kidding!)

You sound like you are somewhat new to the "computer destruction club" (welcome aboard!), so the first thing I would recommend is doing a complete system backup. This will require you to boot the computer from a Linux LiveCD (the Ubuntu disk that you already made should serve this purpose). You should then backup the laptop to an external hard disk. If your family does not have one, this would be a good time to say, "Dad, you know, we should really have an external hard disk. Bad stuff happens you know. Especially with kids." Then run down to BestBuy and get one. At least as large as the harddrive on your biggest computer, preferably at least double that size.

This disaster repair may be as simple as inserting your original Windows disk and doing a "repair installation". But many computers are sold these days without a set of these disks. Data to create them is typically stored on the hard disk. You know, the disk you can't access right now. I am not a Windows expert, and I would not recommend trying something like a Windows repair (that I really know nothing about personally) until after you have a backup of the laptop.

Are your parents computer knowledgeable? Sometimes discretion is the better part of valor and it may be time for you to bow out of the repair process and let your mom or dad handle it if they are better equipped/knowledgeable than you are to do so. Remember, they probably won't actually "kill" you. You will survive (probably).

Luke19 09-19-2013 07:46 PM

Thanks, and just putting it there, I do know about computers and I do know my way around one so I don't really need to ask my parents to do stuff, I have just never used partitioning or Dual-booting, I was liking ubuntu till it got annoying and I done what I was ment to, Create a recovery disk they delete the partition... Could I use my dads laptop, Get my USB and then use universal USB installer, put ubuntu onto it the Repair or Install it again on the free partition?

yancek 09-19-2013 09:54 PM

You're not being too clear about what you want to accomplish. If you want Ubuntu back on the computer so that you can boot it and windows 8, then install it to the same partition you had it on previously and accept the defaults in the installation with regard to the bootloader. Since you deleted the partition, you will need to create a new one during the install. As long as you don't install it on an ntfs partition, you should be back to normal.

If you just want to boot windows, the links I posted above should explain that.
It isn't clear what you made a Recovery Disk of, windows?? It should have a repair option when you boot it.

catilley1092 09-19-2013 10:29 PM

If the repair or recovery disk was made from the option in the Windows 8 control panel, booting into that should give you the option to automatically repair the computer & upon reboot, Windows 8 should fire right up. At any rate, no harm will be done, as long as you don't get into the Advanced tools on the CD.

yancek's advise is good, I have used the option myself to restore a Windows 7 bootloader.

Situations like this is also where haertig's advice in regards to backup is important. All computers should be getting backed up monthly & there should be two separate backups of each, beginning when it is removed from the box & fully updated, but before installing any programs/apps. This image should always be retained, as it gives one a "fresh install" whenever needed. The other can be performed before or after Windows Update (the 2nd Tuesday of each month), I use that day as a reminder.

On my two notebooks with SSD's, they get weekly backups.

You're young & still learning, let this be a lesson to you, backup is an important part of maintaining your computer, regardless of what OS is ran on it. You now see firsthand the penalties of not performing this imperative task. Backup software comes in free & paid versions, though I use paid now, for years I survived on the free backup apps. Macrium Reflect & EaseUS Todo both has a good free backup app for home use only.

Good Luck with the repair CD.

Cat

EDDY1 09-19-2013 11:24 PM

Recovery disks may not be able to repair MBR, you may need to get a wins8 install disk to repair, but keep in mind it has to be the exact same as yours, for instance if you have home premium 64-bit it must be that.
The upgrade disk covers them all.
Whoops it won't work!

EDDY1 09-19-2013 11:42 PM

On the other hand iof you have a usb hdd with let's say Debian with grub 2, which is what I'm working from, you could simply run update-grub it racognizes your wins install then reboot & select wins & you're in unmount usb then repair boot from command prompt. Or http://www.redmondpie.com/download-w...rom-microsoft/

EDDY1 09-19-2013 11:49 PM

This is what I'm saying here
Quote:

sudo update-grub
Generating grub.cfg ...
Found background image: /usr/share/images/desktop-base/desktop-grub.png
Found linux image: /boot/vmlinuz-3.10-2-686-pae
Found initrd image: /boot/initrd.img-3.10-2-686-pae
Found linux image: /boot/vmlinuz-3.10-2-486
Found initrd image: /boot/initrd.img-3.10-2-486
Found memtest86+ image: /boot/memtest86+.bin
Found memtest86+ multiboot image: /boot/memtest86+_multiboot.bin
Found Windows 7 (loader) on /dev/sda2
Found Microsoft Windows XP Home Edition on /dev/sdb2
done
Quote:

sudo fdisk -l

Disk /dev/sda: 320.1 GB, 320072933376 bytes
255 heads, 63 sectors/track, 38913 cylinders, total 625142448 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xbba5daaf

Device Boot Start End Blocks Id System
/dev/sda1 2048 206847 102400 de Dell Utility
/dev/sda2 * 206848 30926847 15360000 7 HPFS/NTFS/exFAT
/dev/sda3 30926848 625140399 297106776 7 HPFS/NTFS/exFAT

Disk /dev/sdb: 160.0 GB, 160041885696 bytes
255 heads, 63 sectors/track, 19457 cylinders, total 312581808 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x34fe34fd

Device Boot Start End Blocks Id System
/dev/sdb1 63 6554519 3277228+ 12 Compaq diagnostics
/dev/sdb2 6554520 48789404 21117442+ c W95 FAT32 (LBA)
/dev/sdb3 48789502 312580095 131895297 5 Extended
/dev/sdb5 * 48789504 52983807 2097152 83 Linux
/dev/sdb6 52985856 67870719 7442432 83 Linux
/dev/sdb7 67872768 73730047 2928640 83 Linux
/dev/sdb8 73732096 82077695 4172800 82 Linux swap / Solaris
/dev/sdb9 82079744 82857983 389120 83 Linux
/dev/sdb10 82860032 312580095 114860032 83 Linux

catilley1092 09-19-2013 11:52 PM

I have successfully used the MBR rebuilder in AOMEI Partition Assistant to rebuild both the Windows 7 & 8 bootloaders (or MBR, as it's called), after a Linux install was removed. There is a tool on there for it.

Sometimes, especially with Windows 8, the install or repair disk doesn't help, though that's the exception & not the rule.

Cat


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