driver.get issues

Hi All,
I am facing some strange issues which i am not even able to find of google.
I have update by driver.get and pass new URL to it but its still taking me to old url

lets say: i had driver.get("http://www.google.com") :- it was working fine
now, i have update my url and make it driver.get("http://www.yahoo.com") but it still navigating to previous url "http://www.google.com".

Does anyone has faced simile issues or any help will be great.

Thanks in advance