Why cannot Ubuntu 12.04 detect windows 7 (dual boot)

Question

I was trying to install Ubuntu 12.04 alongside with windows 7. I only have one hard drive (1TB), and I first installed window 7 on one partition. Now there are about 500GB unlocated space on the disk, and I'd like to install Ubuntu on that part of that partition.

What I did was to boot from a usb stick to install Ubuntu. I have the same problem with the following post.

Ubuntu 12.04 installer does not see Windows already installed on my computer

In the installation, Ubuntu cannot detect the windows 7, so there is no option "install ubuntu alongside with windows 7". I follow the suggestion provided in the above post, and installed the "boot-repair" tool. Then I use the boot-repair tool to create a Bootinfo summary.

Thu url of the bootinfo: http://paste.ubuntu.com/1057933/

I also use "try ubuntu" to use the terminal. When I type "sudo os-prober" in the command line, it returns nothing. It seems that ubuntu cannot detect the installed windows 7.

Since my situation is different from that in the previous post. I only have one hard drive, so the problem should not be related to any raid thing.

Can anybody help me on this? What can I to make ubuntu to detect the windows 7.

Solution

1. Your PC uses a recent boot system (EFI), which may be why GRUB (which uses os-prober) did not detect Windows. This is a bug of os-prober that should be reported here.

2. Repair your Windows boot by booting on a Seven Recovery CD (32bit or 64bit), then type these 2 commands:

   bootrec /fixmbr

   bootrec /fixboot

3. When you recovered direct access to Windows, use Boot-Repair to recover the GRUB menu

Comments

[atenz]

Why don't you try custom installation by defining Ubuntu's partitions manually .After installation completes , i am pretty sure it will be sorted out .If not then run sudo update-grub from installed Ubuntu OS.

[atenz]

Fine , post this as your answer and accept it. So others having having same problems can sort out.

[Jerry]

Thanks. It seems that I have to wait for 10 hours to answer the question since I am new.

[Jerry]

New problem appears. After the installation, if I select to boot windows 7, it can not start....... eh! It says there is some error and I need to repair the windows. Maybe it is because that I choose the "recommended repair" of the boot-repair tool?

[atenz]

Does it boot normally even if it shows repair option. I guess its fine , windows does panic at such manual boot repair.

[Admin]

I've been having the same problem.