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I recently got a new HP Laptop with Windows-7 64-bit pre-installed on it. It has a 500GB SATA hard drive. The partitions(as I got them when purchased) were as follows:

C:\ = NTFS (Around 32 GB used). Free space here as around 407GB.
D:\ = Recovery partition for Windows.(Around 17GB used)

Then I wanted to install Ubuntu while keeping Windows-7. So I booted with a Ubuntu LiveCD. It reached a stage during the Ubuntu setup, where it asked for partition to install Ubuntu. It showed below partitions :

/dev/sda1 - NTFS - 208 MB Windows 7 Loader.

/dev/sda2 - NTFS - 482GB 
This I thought was the C:\   NTFS partition.

/dev/sda3 - 17.6 GB Windows-Vista loader  
Above partition I guessed was the Windows recovery partition(Correct me if wrong)

/dev/sda4 - 108 MB  

Here I chose advanced option, as the only other option was Erase full disk and install Ubuntu, which I did not want. In the advanced option, I selected /dev/sda2/ and said 'Change' it. then allotted 50 GB of that 482GB to Linux and formatted it as ext2 file system. Then after formatting this it said writing the changes in file system to hard disk. After this it showed me /dev/sda2 as ext2 and below that it showed a partition with no name(sda??), neither partition type (NTFS/ext2) nothing, but next to it was written 'Unusable' size 420 GB. I figured that this is the NTFS partition which was resized and tried to format it to NTFS but there was just no option to do it. So I continued Ubuntu installation . It went through successfully. Then When I rebooted, Grub loader provided me below options :

Ubuntu 10.04

Ubuntu 10.04 (recovery mode)

Windows 7 Loader

Windows Visa Loader

Memory Tests.

When I selected Windows-7, it said starting Windows, but could not load Windows. But after some time it gave error saying Startup repair trying to repair the disk. Basically my Windows OS/Loader was corrupted and no more usable.

My questions are:

  1. What did I do wrong during Ubuntu installation disk partitioning & formatting which caused this problem?

  2. What exactly is the problem ? What should I have done/not done to avoid this problem?

  3. Without having to reformat and reinstall or restore Windows to old state9which means Ubuntu will go away), can I salvage both OSes?

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up vote 1 down vote accepted

It looks like you have more than four primary partitions, you need to remove some so you have no more than three primary, then add an extended partition with the additional required logical partitions.

Using a boot CD like Parted Magic you should be able to back up your data, you can then use GParted to remove the 420GB partition and one of the others, the recovery one if you've created recovery discs from it. Then create an extended partition in the free space where you can reinstall Ubuntu.

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Sounds like the resize of the large ntfs partition is what put the whammy on windows
I've never used that feature on ubuntu, so I can't speak to how well it works.

I think your windows partition is already hosed. As far as I know, the win7 bootloader partition is not all of windows, it's enough for win7 to initially load and initialize the hardware, and then it can read anything else it need from the c partition. If C is hosed, then windows can't finish booting. You can try booting off of a windows recovery cd, and see if that will help, or off of a live linux cd, like RIPLinux, or Knoppix. Since it sees the partition at the reduced size, but as unknown, the data might be there and the partition table may just be messed up. You could try re-writing the partition type with fdisk and see if that works.

Whenever you resize a partition, best practice it to back it up(using acronis, clonzilla, etc.), in case the resize messes up.

Personally, I would just wipe the drive, reinstall windows to the size that you want. Then, make a backup of the windows install(both the bootloader partition,and the c partition) to an external usb drive with acronis, and then install ubuntu after that.

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Thanks. But even if I clean install windows, backup windows data/partitions, and then try to install ubuntu, it could stil go wrong, if I don't know what is the correct way to do make a linux ext2 partition for ubuntu install. That is what I wnat to know. ! – goldenmean May 19 '11 at 23:20
  • I think you must have chosen the wrong partition.
  • I'm not sure what the problem is exactly, but I believe you should have used Ubuntu's Windows installer to install Ubuntu, as it will install a large virtual hard drive file inside C:\ubuntu, which will not interfere with Windows 7.
  • The only thing you can do is to copy your files from Windows on to a USB thumb drive through Ubuntu and reinstall Windows:

    1. boot from your Ubuntu CD/DVD and choose to try Ubuntu.
    2. Insert a USB thumb drive after you get to the desktop.
    3. Now go to Places > Computer and keep opening hard drives until you find one with a "Windows" folder in it.
    4. Go to "Users" followed by your username and you can copy and paste anything from there into the thumb drive. Copying Desktop, Documents, Music, Pictures and Videos should be fine.
    5. Now place your Windows 7 recovery disc in the drive, restart your PC and reinstall Windows.
    6. Copy files from your thumb drive to where you copied them from.
    7. After it is installed, use the above link to install Ubuntu.
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