unable to add entity framework package to visual studio 2010!

hello all,

i am working on one MVC 3 application where i want's to careate model and for this i have done is as follows :

In Visual Studio 2010 go to Tools -> Library Package Manager -> Click on Add Library Package Reference...

This will open new window as Add Library Package Reference.

Click on Online in left pane and try to find EFCodeFirst package...

i am getting following error and not able to find it :

The remote server return an error: (407) Proxy Authentication Required.

I have set my local machines Windows Firewall off, still no luck.

Please help me on this...

Thanks,

Nilesh.