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Downloaded ubuntu-12.10-desktop-amd64.iso from official website and created the bootable pen drive using Universal USB Installer. Then I booted with it and when asked to select installation type, I selected 'Something Else'

I have Windows 8 OS already installed on this laptop with Intel i5 processor. Is my selected option 'Something Else' right?

I want Ubuntu to install in the selected ntfs drive /dev/sda6. But when I pressed Install now button, an error occurred saying:

No root file system defined. Please correct this from the partitioning menu.

Any help would be really appreciated.

PS: I'm new to Ubuntu as well Linux itself.

share|improve this question
We can't see your images. Can you upload somewhere, and add the links, and I'll add them for you. – Mitch May 8 '13 at 18:04
Without the screenshots I can only guess, but I think your partitioning incorrectly. You should probably use one of the easy choices though that will erase windows. If you really want to manually partition, then make sure you add at least a 10G partition with a mount point of / and a type of ext3. Also /dev/sda6 is a partition. If you want to install on a whole device you want /dev/sda (careful though, that could really mess things up if you intend to dual boot) – coteyr May 8 '13 at 18:12

You have to set your mount point, means the point where to install ubuntu (kind of). You may do this, but please, first notice that all data on the selected partition will be deleted, and the file system will be changed from NTFS to Ext4. You may want to save your most important files to a USB stick or make some other kind of backup to be sure. If there is another operating system on the selected partition, it will also be deleted, but you can let go of "something else" in this case and choose what you want to do. My guideline assumes you already have a partition where there is nothing important on it.

  • choose the partition you want to install ubuntu on, by clicking on it.
  • click on "change". A new little window will appear.
  • for "Use as:" choose "Ext4 journaling file system"
  • for "Mount point:" choose "/" (called root)
  • click on "OK" and then on "Install now".
share|improve this answer

When you make a custom partition scheme, you should first make space on the disk by reducing the size of an existing partition. Then you create a partition in the unallocated space. Then you select that partition and choose the mount point. It sounds like you did not perform this third step.

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This is more a comment than an answer. – user68186 May 8 '13 at 18:51
@user68186 I think this is the the answer that Veer needs. The error message results when the moint point is not selected. – Konstantin Schubert May 8 '13 at 19:10
@Konstantin The point may be correct, but the answer does not tell the Veer what format the partition should be and what mount points to choose. The answer also need something about the swap partition. – user68186 May 8 '13 at 19:15
@user68186 I just answered to Veer where is the "Installation problem…!". It's just a simple answer. Maybe just knowing this, Veer can handle it. If the question would be requested a more detailed answer, I'd probably be offered (and this is a comment). Anyway, the answer can be voted down (I will delete it myself in this case) or flagged or deleted by moderators if is not ok. – Radu Rădeanu May 8 '13 at 19:45
@user68186 My computer works great with Swap: 0 0 0 (just reported by free command) and I had no installation problems. – Radu Rădeanu May 8 '13 at 20:01

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