cannot navigate within sites

[mazinger]

Hello and thanks in advance for any help anyone can provide.

since two days what is happening is that I can go to a site lets say,

http://www.411.ca

and i would be able to get in but when i try to naviogate within, i get the unable to find the server message. but i cant goto google.ca at all whereas msn.com or

http://www.thestar.com

is no problem and i can surf their entire contents of the site.

any settings that I touched on by mistake that is causing this?

many thanks.