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I have finally installed Ubuntu on my second drive. When I start my computer GRUB only offers me to boot Ubuntu, not Windows 7. What needs to be done so that I can choose between Ubuntu and Windows in GRUB?

When I press F12 for boot menu at startup and I choose Windows Boot Manager it boots into Windows 7.

I ran command sudo fdisk -l and here is log:

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Please indicate your Boot-Info URL. This will provide relevant information to help you. – LovinBuntu Oct 9 '12 at 9:30
  1. Boot Ubuntu and mount your Windows partition (simply open the disk on Nautilus)

  2. Run the following on the command line (Ctrl+Alt+t):

    sudo os-prober
  3. If your Windows installation was found, you can run:

    sudo update-grub

Note that step 2 is just for your convenience. You could just mount the Windows 7 partition and then run update-grub.

Related question

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I have 2 partitions with 2 windows install, it only detects my install on another partition, but not the new installed windows (on a SSD)! even mounted... an idea? – Philippe Gachoud May 29 '15 at 9:00

If the os-prober method above doesn't work try to add a custom grub menu entry

documented here edit the /etc/grub.d/40_custom file

menuentry "Windows 7" {  
     insmod ntfs  
     set root='(hd0,1)'  
     search --no-floppy --fs-uuid --set a3f1ea41fc67a3f1  
     chainloader +1  

to get the uuid you can to use the blkid /dev/sdx command

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I solved a similar problem following steps of Boot-Repair

Install boot-repair

sudo add-apt-repository ppa:yannubuntu/boot-repair
sudo apt-get update
sudo apt-get install -y boot-repair && boot-repair

Push "Recommended repair" And put in a terminal some commands as it suggested.

I think my Grub doesn't recognize windows due to a bad shutdown, and it solved the problem.

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