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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 HDD. 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 Win-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 alloted 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 throught successfully. Then When I rebooted, Grub loader provided me below options :-

Ubuntu 10.04

Ubuntu 10.04 (recovery mode)

Windows7 Loader

Windows Visa Loader

Memory Tests.

When I selected Windows-7, it saud 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?

Any pointers useful.


merged by Sathya May 20 '11 at 4:46

This question was merged with Partition error after installing Ubuntu on a Windows-7 Laptop because it is an exact duplicate of that question.

migrated from May 19 '11 at 23:13

This question came from our site for system and network administrators.