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I downloaded mac osx virtual disk image for virtualbox and i made a new machine and atached the new virtual hard disk. The problem is that the mac osx virtual hard disk had 150GB and my whole hard disk memory is 160GB. After reboot I get the error unknown filesystem. When i try to acces my partitions i get the error unknown filesystem and i don't find my ubuntu files and folders. What to do? Any chance to get back my files?


I tryed this command without succes:

sudo mount -t ext4 -o errors=continue /dev/sda2 /mnt

Here is the output of fdisk -l

Here is the output of blkid

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Here is the error of the mount – Codrut Oct 28 '12 at 8:32

It sounds like the filesystem is failing to mount. You can boot off the LiveCD and try deleting the disk image on the drive, then try booting off the hard drive. The VitualBox disk files can normally be found in ~/.VirtualBox/HardDisks (note dotfile and capitalisation). Another place that Virtual Disks are stored is '~/VitualBox VMs' depending on whether you are running the opensource or PUEL version of VirtualBox.

To force the mount you may need to open a terminal window and type:

sudo mount -t ext4 -o errors=continue /dev/sda6 /mnt

This will mount /dev/sda2 on /mnt in read/write mode. Given that the filesystem appears to be messed up it might be better to mount the device in read only mode if errors are encountered so that you can backup any important data on /home

sudo mount -t ext4 -o errors=remount-ro /dev/sda6 /mnt

It's better to seriously limit the size of VM disks so this kind of thing can't happen but if this is not possible you should use dynamic sizing, and either have a /home partition that is separate to the / partition, or put the VM disks on a completely different data drive from either.

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I can't accest my partition, I tried from grub rescue and with a live usb with LuPu an ubuntu based pupy linux. Here are some pictures: From grub rescue I get the unknown filesystem error when I try to acces any partition so i can't find my files. – Codrut Oct 25 '12 at 16:13
See the updated instructions. If you're not sure about the instructions or run into problems give the output of 'sudo fdisk -l' and 'sudo blkid' in the body of your question so that we can see what your filesystems looks like. – fabricator4 Oct 25 '12 at 18:42

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