Ubuntu - missing operating system [closed]

Question

I had a fully working Ubuntu system which I wanted to resize in order to be able to install Windows. Using Live CD I managed to resize the primary dev/sda1 and create space for windows. Once I installed Windows I've seen that the system was not letting me to choose the OS at startup. I re-opened the Live CD, moved the boot flag from Window's partition to dev/sda1 and here I am: Missing operating system.

I believe this is a problem concerning grub but I don't have the slightest of what to do and where to look. I'd appreciate help!

Answer 1

You may want to check this official page. The documentation is pretty easy to follow.

In any case, if the link dies, I describe the procedures to recover the grub settings.

 1. Login to Ubuntu using Live CD. 
 2. Open a new terminal (should be shift+alt+t).
 3. Add this repository: sudo add-apt-repository ppa:yannubuntu/boot-repair && sudo apt-get update
 4. Install boot-repair: sudo apt-get install -y boot-repair && (boot-repair &)
 5. Run it and click recommended settings. Wait a few seconds and when it tells you to do so reboot the computer. You should be done.

Let us know if this solves your problem!