I've messed things up a bit.
I was running Windows 7 ultimate 64-bit in my HP laptop. I was using live USB of Ubuntu 11.10 and then I tried to install Ubuntu on hard disk using the same live USB.
To install Ubuntu, I chose 50 GB free partition and 325 GB swap space or something.
While installing Ubuntu, my pen-drive came out and everything stopped. Then I booted again using the pen-drive and finished installation of Ubuntu.
Now the problem is I can't access my Windows partition as they were in extended partition plus I am not able to boot Windows 7 from the booting screen and I can't even repair or recover it.
Whenever I try to boot Windows it shows the message
HARDWARE INACCESSIBLE, TRY TO REPAIR YOUR WINDOWS USING DISC. When I tried using disc, there was no instance of OS available to repair.
I can't even install fresh Windows 7 as the setup asks me to load drivers of Hard disk.
I have important data in the Windows root drive as well as in other partitions. How can I recover that data?