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I want to dual boot Ubuntu with Windows 8 Enterprise.

I have a 160 GB Hard Disk Drive and completely wiped out all the existing partitions of this drive to create 3 new partitions in the following order:

  • 30 GB (for Ubuntu)
  • 35 GB (for Windows)
  • 84 GB (balance for other documents)

Next, I installed Windows 8 on the 2nd partition of the drive; ie; the one with 35 GB.

Then, I booted Ubuntu 12.10 off my USB Drive to install it on the 1st partition of the drive; ie; the one with 30 GB. When it asks for Installation Type, I select Something else and press Continue.

Ubuntu 12.10 Installation Type

The following screen shows the partitions on my Hard Disk. However, I notice that Windows is also utilizing a bit of space in the first partition on which I want to install Ubuntu. And probably Windows Boot Manager files also reside in this partition.

Partitions shown by Ubuntu

Following is the snapshot from Windows Disk Management.

Partitions shown by Windows

So, my fear is that if I install Ubuntu on the 1st Partition, then I would lose the ability to Boot into Windows. Please help me with what are the options available for me and how I should go about installing Ubuntu in order to make Dual-boot a success.

  • Will installing Ubuntu on this 1st Partition and then running bootrec /FixMbr from Windows Recovery Command Prompt fix the problem?

  • Or, shrinking this 1st Partition is the best solution? If so - what size should it be?

  • Or, something else all together.

  • Or, all my fears are baseless and I should just go on with the installation?

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You made a slight mistake that got you confused: you should have deleted the partitions and only format the 2 you installed Windows (35) and your documents (85) on. Then you would have seen a slightly different image for gparted (where it would state 'empty' for sda1).

Install Ubuntu on sda1 by deleting sda1 and formatting it to ext4 (or less preferred ext3) where you divide sda into 3 parts: / (something like ... 10 Gb), swap (2 Gb) and /home (18 Gb)). (you will thank me someday for suggesting a separate partition for /home ;) )

So to answer the question: Or, all my fears are baseless and I should just go on with the installation? is the correct one. But you might need to fix something in grub to get Windows back. The fixmbr will remove grub and therefor Ubuntu from the boot list.

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up vote 1 down vote accepted

To answer this question

The best option was to shrink the 1st Partition to a size of anything more than 350 MB [Windows would use this partition as System Reserved and store other critical files which are related to its installation]. Then do a normal install of Ubuntu. Following this simple step would have made Dual-boot a success.

Now coming to what I did and how I came to this solution

  • I simply installed Ubuntu on that 30 GB partition. As such all the files which were stored by Windows on this partition got erased and I was left with no choice which would have allowed me to boot into Windows.
  • I was already prepared for this situation, so inserted Windows Installation DVD and booted from it. I went into the command-prompt and did bootrec /FixMbr and did a reboot. This removed Grub and as such I wasn't able to boot into Ubuntu (I knew that). However, this didn't fix the problem. I was staring at my screen which said that it didn't find any Operating System. So, bootrec didn't solve the problem.
  • I booted off Ubuntu's Live USB. Went online and found that bcdboot might help me solve the problem. However, running bcdboot c:\windows /s c: didn't help my issue. As per Microsoft Technet:

    bcdboot: Enables you to quickly set up a system partition, or to repair the boot environment located on the system partition. The system partition is set up by copying a simple set of Boot Configuration Data (BCD) files to an existing empty partition.

  • I again booted off Windows DVD; this time tried to Refresh the installation of Windows, but it said that "The Drive where Windows is installed is locked. Unlock the drive and try again.".
  • Then tried to Reset the installation of Windows. This time it complained something about that I don't have a necessary partition. [This was so because all the available space was utilized in installation of Ubuntu. When we install Windows it tries to find unallocated space on disk to create a System Reserved partition of 350 MB. This was the problem when I first installed Windows before asking this question. I had allocated all the space on drive to different partitions. Hence, it used the 30 GB partition to store the files which it stores in a System Reserved Partition.]
  • I understood the issue and completely deleted both 30 GB and 35 GB partitions. Recreated the 35 GB partition and left the rest of the space unallocated. Then, installed Windows and found that it had automatically created a System Reserved Partition of 350 MB out of the unallocated space. Then, installed Ubuntu normally and everything works like charm. [I could also have resized / partition of Ubuntu to create a 350 MB free space; then installed Windows; then do a boot-repair. This would have had the same effect.]

In a Nutshell

We should leave some space (more than 350 MB) unallocated on our Hard Disk (preferably at the start) before installing Windows. Following this step should solve all the problem.

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