Many of the desktop users are using windows and linux in same system simaltaneously like me. My desktop is used by me and my younger brother, so its difficult to use linux for him,thats why he used to access windows. Today i installed windows 8 for him and afetr installing i faced a problem that while booting i missed the prompt : what to choose( linux or windows). That was a simple boot-loader error which was ocurred after installation of windows. I think many of the dual boot users face this problem . Okay not to worry. heres the solves.
you need the linux installation bootable disk image. 12.04 or higher ( for ubuntu) is preferable. Insert the installation cd/dvd and boot the dvd. then you find two options installing ubuntu or try ubuntu. you dont need to install ubuntu. as you are a existing user and you dont want to lose the previous data, you just need to repair the boot loader.
choose try ubuntu. and come to the home of ubuntu. you need to download the repair boot loader, so edit your internet connection in the network configuration menu, you need to enable the internet connection in try ubuntu. add/edit your connection settings as per your ISP ( mobile broadband/dsl cable/wireless/wired). Now enable your internet connection.
Open your terminal. Type the following command :
sudo add-apt-repository ppa:yannubuntu/boot-repair && sudo apt-get update
It will take a time depending the speed of your ISP. After that the download process will be successful and you need to install the file. Then type the following command:
apt-get install boot-repair
Thus it will install the boot repair. you can check if its installed or not by going to search and typing “boot-repair”. you will see the application there, now open the application. It will detect the problem and will suggest you to confirm some permittion, make sure to confirm and after a short time, you get the message “Boot repair Successful”.