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When I try to install Ubuntu 10.10 from the official livedisc I got in the mail, when I get to the "Allocate Disk Space" step I cannot get it to work. I shrank my win7 partition so I have unallocated space, then I tried using the space while it is formatted in NTFS, but the partitions will not show up in the box. /dev/sda is selected under boot loader, and I can't select anything else, but the partition box is blank so when I click "install ubuntu" it just says: "No root file system is defined. Please correct this from the partitioning menu."

-I am trying to dual-boot win7 and ubuntu, but I was never asked in the install process whether I would like to install just ubuntu or dual-boot?

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You chose manual partitioning and the box does not show /dev/sda? – psusi Feb 3 '11 at 3:37

Open a terminal


sudo apt-get remove dmraid

then type "y" then enter"

This TOTALLY worked. I did it all from 10.10 cd. Must be some RAID code interfering with the install - the new installation is terrible. Thanks for the help.

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This worked for me. It is from . Go to the bottom and read the following: "Ultimate solution:

Boot up 9.10 Live CD

Open a terminal

type: sudo apt-get remove dmraid

then type "y" then enter

now try to install!" This solved my problem and hopefully for all of you folks also!

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THANK YOU!!!! This did work, I did this and was able to install 10.10 successfully with the Live CD. – user10134 Feb 8 '11 at 5:49

i guess you are doing it wrong. dont install ubuntu without reading the manual for advanced partition. you will end up deleting win 7 altogether! check this tutotrial.

it is based on ubuntu 9.04 but idea is the same. you need to create 2 partitions. one for swap and another for root. check the screenshots in that tutorial. if u still have confusion, come back and post q's again.

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When I try to install it, it never shows me this step… I don't get the option of how I want to install it, instead it goes to a screen where it wants to prepare the partitions, but doesn't show the partitions.… this is what it brings me to instead of showing me that step, but the bar at the top is empty, the box is empty, and I can't select anything besides /dev/sda – user10134 Feb 5 '11 at 2:45

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