Following are the steps till I purchased my computer
- Installed windows 7
- Installed Ubuntu
- There was no boot option, and ubuntu automatically boot, leaving me no option to boot my windows
- I used windows repair to repair MBR or whatever it is
- Now, ubuntu does not boot, there is no option to boot ubuntu
- Finally, I used boot repair disc.
- Now, there are options for windows and ubuntu.
- ubuntu boot properly.
- Windows boot but there is blank PURPLE screen after that
Here is the link: