I installed ubuntu 12.04 after installing windows 7. I have 2 hard disks, one SSD and another HDD. Windows was installed in the HDD, and I wanted ubuntu on my SSD. I chose to have boot files in the SSD where I had installed ubuntu. Initially after the installation it didn't show the dual boot option and directly booted to ubuntu. But after going through some suggestions I used boot-repair and got GRUB repaired/installed. But when I restarted again in the boot options I didn't find the Windows 7 option. I fear that I have accidentally deleted the windows boot files. This is the link I got after boot-repair: http://paste.ubuntu.com/1615740/
Looking at it a bit more, I suspect that running the following command in the Windows 7 installation CD repair console will allow os-prober to find your windows installation.
After running the command. Reboot, you will most likely still only boot into Ubuntu. So then rerun the boot-repair script. If you've got any trouble please submit the new pastebin.
You can try rebooting after manually modifying your grub menu very, very carefully by opening Terminal and entering
If this works, you can make this menu entry permanent by performing the same insertion on the file "/etc/grub.d/40_custom" with this Terminal command:
This might serve as a workaround if this is because your Ubuntu/Grub somehow cannot detect Windows.