netscape firefox!Ie is not connecting to internet but firefox and netscape connects?

Could any one help me in this. I have IE8 ,firefox and netscape browsers. both firefox and netscape connects to internet but not ie, i am having vista operatingnetscape firefox system. pls helpme.
OK Goto IE settings > Find a tab called Network > Settings > Auto Detect.
firewall problem firewall not set to allow IE8 to connect
Younetscape firefoxr IE browser is most likely infected with a virus or trojan. Firefox is by far the best browser anyway, and is well-known for its security and efficiency.