It so happened that after installing windows on my system (which already had linux, ubuntu, installed on it), the grub menu that used to come at the beginning stopped appearing. Instead, it started to boot directly into windows.
In order to solve this problem, I did the following. Of course, I found a lot of answers to this problem on the net, but what I did worked for me fine. But be sure to sit patiently and correct it in case something does not work fine. Never give up!
(Note: I also do believe that the following works only when the ‘vmlinuz’ and ‘initrd.img’ files are at the root directory itself. Check this in step 5. In step 5, ‘vmlinuz’ and ‘initrd.img’ should be there in the ‘temp’ folder we created.)
1. Boot using a live cd of ubuntu.
2. Open a terminal and run the command
sudo fdisk -l
It lists the complete partition table of the hard disk. In there, identify which partition you have got your linux installed on. You can identify it using the drive size you had allocated for it and looking at the last column of the output which will be ‘extended’ for all of your linux partitions. The partition will most probably be something like /dev/sda5 or something. Remember this partition.
3. Create a temporary folder in your home directory (Note: You can make the temporary folder anywhere you want. I’m using the home folder just for the sake of explanation). I’m calling it ‘temp’ for now. So that ‘temp’ folder’s path will be /home/ubuntu/temp.
4. Mount your linux partition there. That is, assuming that you found your linux partition to be /dev/sda5, you mount that at the ‘temp’ folder by doing the following command
sudo mount /dev/sda5 /home/ubuntu/temp
5. If you want to check whether you have mounted the correct partition, go to your home folder and open temp. You will be in the ‘/’ directory. In there you will find ‘home’, in which your home folder’s name will be there. Once you’ve confirmed you have mounted the correct partition, do step 6.
6. You have to install grub by showing the system where to read the data from the hard disk at the beginning. Don’t worry, just run the following command
sudo grub-install –root-directory=/home/ubuntu/temp /dev/sda
The ‘/dev/sda’ corresponds to your hard disk name. Replace it by whatever the command ‘sudo fdisk -l’ command showed you.
7. You’re done. You may restart your system.
You might want to check out how I upgraded to 12.04 too!
PS: For editing the grub menu that appears, check out my post