I reinstalled Windows 7 today. I have a live USB with Ubuntu 13.04 made with universal USB manager. I want to install Ubuntu alongside Windows 7.

I have 320GB hard drive in which 100 gig is for Windows (already allocated), 120GB for my files (already allocated), 100GB for Ubuntu (yet to allocate).

I don't get the option dual boot with Windows 7 while trying with live USB (Ubuntu 13.04).

I tried selecting the 100GB unallocated and in NTFS format in the Something Else option, but it says no root file system selected.

Why don't I get the option to install Ubuntu alongside Windows and how can I fix this?

  • You have to be more specific. 1) If you want to boot from your USB you have to make sure that it is set ahead of the HD where you have W7 in the BIOS boot order; 2) If you installed W7 after Ubuntu, and had GRUB bootloader, you replaced it with Windows Boot Loader that doesn't recognize Ubuntu; and 3) if you want to install Ubuntu now that you have W7 installed, you can't do it on a NTFS partition, and definitely not on unallocated space. You need to create a ext4 partition with the installer and set the mount point to /. Jul 31, 2013 at 15:40
  • Did you create partitions with Windows? And if it converted to dynamic then it will not work with Linux. You cannot install Ubuntu into NTFS partitions except with wubi, which is not what you want. You need to create partitions during install as ext4 or with gparted from live installer.
    – oldfred
    Jul 31, 2013 at 17:19
  • OK now I have 100gb unallocated I want to access the drive both in windows and ubuntu how do I partition it? With what? And how explain in detail. Aug 1, 2013 at 1:41

1 Answer 1


If you have an available primary partition to be the extended partition, then you can install Ubuntu and create a shared NTFS data partition for data. All partitions will be logical partitions inside the extended partition. I prefer to set up partitions with gparted in advance so I better know sizes. But all but the NTFS data partition can be done as part of the install.


GParted partitioning software - Full tutorial


For the Total space you want for Ubuntu: Ubuntu's standard install is just / (root) & swap, but it is better to add another partition for /home if allocating over 30GB.: Ubuntu partitions - smaller root only where hard drive space is limited. If total space less than about 30GB just use / not separate /home or standard install.

  1. 10-25 GB Mountpoint / primary or logical beginning ext4(or ext3)
  2. all but 2 GB Mountpoint /home logical beginning ext4(or ext3)
  3. 2 GB Mountpoint swap logical

Depending on how much memory you have you may not absolutely need swap but having some is still recommended. I do not hibernate (boots fast enough for me) but if hibernating then you need swap equal to RAM in GiB not GB. And if dual booting with windows a shared NTFS partition is also recommended. But you usually cannot create that as part of the install, just leave some space. Or partition in advance (recommended). One advantage of partitioning in advance is that the installer will use the swap space to speed up the install. https://help.ubuntu.com/community/DiskSpace

  • I have a installed windows 7 in a 100 gig partition,allocated 120 gig for my data and files the rest 100 gig is free and it is still not partitioned. All the created partitions are primary partitions. I have a 4 gig ram. How much memory should i allocate for swap... WHY IS INSTALL ALONG WITH WINDOWS 7 OPTION NOT SHOWN? Aug 2, 2013 at 13:32

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