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I have an HP Desktop AMD 64 6-core processor 10GB RAM 1.5TB HDD and Windows 7 installed. I downloaded the 12.04 ISO and burned to a DVD.

I want to install Ubuntu over Windows. I have recovery CD's made in case Ubuntu isn't for me and my family. During the install it says No root file system is defined please correct this from the partitioning table.

In the box where I should be able to choose a partition, none are available to choose from, it is blank. I know that HP has decided to use 4 partitions. How do I go about deleting all the partitions using the LiveCD? I've never used GParted before and am a bit lost when it comes to anything to do with partitions.

After following your directions completely, when I choose to install, I still have the same problem. No partitions show up to install from. It's just a blank box and I still get the same error.

In Gparted it show:

Partition File System Label Size Used Unused Flags

unallocated unallocated 698.64 - - /dev/sda1 ext2 / 698.63 11.03GiB 687.60 boot unallocated unallocated 2.49 - -

I close out Gparted and then click Install Ubuntu on the desktop. It asks me to choose a language, make sure i'm connected to the net, download updates, install 3rd party software. I click next. Then the option to choose where to install it comes up, however there is nothing to choose from. At the bottom it says /dev/sda. I click install and it gives me the error "No root partition is selected check your partition table" ???

I am not getting an Installation Type choice on the third screen. I do not know how to take screen shots of what I am doing either, so I am doing my best to spell out what is happening:

On the desktop I open the shortcut that says "Install Ubuntun 12.04.1 LTS.

The first screen that appears says Welcome and it asks me to choose a language. I select English and click Continue.

Screen 2 says Preparing to Install Ubuntu. For best results please ensure that this computer has at least 4.5 GB of available space - Check Is connected to the internet - Check Download Updates while installing - Checked the box Install 3rd party software...mp3, flash etc... - Checked the box

Screen 3 says Installation Type.
There is a box that apparently should show where the OS is going to be installed to.
The top of the box says Device, Type, Mount point, Format? Size, Used Below that is a large empty space Towards the bottom there are buttons "New Partition Table... Add... Change... Below that it says Device for boot loader installation: /dev/sda

Then on the bottom right of screen is Quit, Back, Install Now.

The first two buttons at bottom are obvious, but when I click "Install Now" I get the following error:

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

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Did you select the "Erase disk and install Ubuntu" option which is on the third screen of the installation process? – Peachy Sep 23 '12 at 13:55

If you want to get rid of Windows completely, then in the partitioner right-click each of the HP/Windows partitions and delete them. Next, create a new partition. Here is an image of what the options may look like:This is an older version of ubuntu, but should work

When presented with these options, choose "Primary" for the "Create as:" option. In the section "New size (in MB)" put the amount of MB that equals the size of your hard drive - 1000mb. Set "Filesystem" as Ext 4. There should be a section to define the partition. Set it as root, which is represented as "/" Make the second partition as "swap." Make it the size of the remaining amount of unpartitioned space. I'm telling you to put such a small amount of swap assuming you have a relatively new computer (3-4 yrs?). Swap is hard drive space used in UNIX operating systems that gets used as RAM. You don't even need it really.

/ represents your entire hard drive outside of swap. It is the equivalent of the "C" drive in Windows. Newbie distributions of Linux like Ubuntu use only / and swap to make partitioning easier. I run Arch and use four partitions: /boot, /, /home, and swap. This is not necessary is your are running ubuntu for the first time. You can get away with using only /.

NOTE: For root /, be sure to mark it as bootable. If you fail to do so, your computer will not be able to boot. IIRC, you right click on that partition and toggle the "bootable" flag. It has been a while since I have played around with Ubuntu. Good luck!

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If you really want to completely replace Windows, just choose "Erase disk and install Ubuntu" on the third screen of the installation process as shown below. There is no need for you to delete existing partitions.

enter image description here

After which you'll see the selected disk and partitioning scheme that will be used. You can click on the "Select drive:" box to change the selected drive. As you'll see Ubuntu will be installed on the entire drive with ext4 file system.

enter image description here

Then click on "Install Now" to complete the installation process.

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