I am using windows 7 ultimate. I want to install ubuntu as a dual boot on W7. I have installed EasyBCD. but when I run EasyBCD It shows the following error message.

(I have named my system reserved disk as X and foud BCD file in it.) I clicked on "yes" on the above Error. But when I tried to load BCD manually, it again shows the following message.
When I click on "ok", EasyBCD stops. Where am I going wrong?
What should I do to correctly install dual boot on my PC?
Please help!
Thanks in advance.

(I have named my system reserved disk as X and foud BCD file in it.) I clicked on "yes" on the above Error. But when I tried to load BCD manually, it again shows the following message.

When I click on "ok", EasyBCD stops. Where am I going wrong?
What should I do to correctly install dual boot on my PC?
Please help!
Thanks in advance.