Ubuntu 12.04.3 not booting

Question

I installed ubuntu 12.04 (in Window 7 machine) and it was working properly. I recently did try to install Picture editor sw, before it finished it asked to ["recovering something"...I cannot recall..Or "Cancel"] And I Clicked "Recovering..." instead of "Cancel". Then the screen becomes blank with a cursor blinking on it.And now it won't complete the boot-up process, the screen keep on being blank with a cursor blinking on it.. What is the problem?

On the other hand, Windows 7 is working properly

Answer 1

Could you have messed with some important files? This has happened to me when I tried to install a program (no need to mention which) and just because it got stuck in the middle, Ubuntu wouldn't boot.

1st Option: Boot Repair

Please see this https://help.ubuntu.com/community/Boot-Repair in order to fix the boot process. If this doesn't work, you'll probably have to install Ubuntu again.

2nd Option: Reinstalling Ubuntu

You probably know what to do, but in case you have important files stored in your Ubuntu installation, see this How to access Ubuntu files in Windows 7 while having dual boot?.