Sign up ×  I had Windows 7 and Ubuntu both installed on my
machine, but for some reasons I re-installed Windows 7, and now
when the system starts, I can't see GRUB menu, which normally
appears asking using for windows or ubuntu OS.  How to bring
that menu back?   share|improve this question  2 Answers 2  If
you reinstalled windows, now you have its bootloader which
conveniently doesn't detect Linux OS's, and not Grub.  To
reinstall Grub, with all the options you had, you'll need a
linux live CD or pen. Once in a "live session":    1. Open a
Terminal   2. Use sudo fdisk -l and locate Ubuntu's partition.
3. Mount said partition in /mnt (replace XY, with the correct
letter & number):     • sudo mount /dev/sdaXY /mnt   4.
Reinstall grub (assuming /dev/sda is your main HDD):
share|improve this answer  It should definitively have be asked
before, but cannot find a reference.  By the way, it is a normal
situation, answered here.  share|improve this answer  Your
Answer