Browsers can't to connect to internet..!!

I have a Windows 7 installed at Home. With 4 browsers : IE 9, Opera 11.50, Firefox 6 and Chrome 13.078. Now here's the problem, every program installed in machine can access the internet, Antivirus (Avast Free 6), Torrent, Windows Update, Firewall (PC Tools) and others too, BUT, the browsers. They just can't access the internet ! I've checked the Firewall settings too, they're all OK. Also went through malware check (SUPERAntiSpyware) and it's all clean. Please help here!

Maguscreed said:

I'll stick with the browser I'm familiar with.
In firefox open options tools - options
click the advanced button at the top, then click the network tab.
click the settings button beside 'connection'
Try both use system proxy, and auto-detect proxy, to see if either will obtain a connection.
If a bunch of proxy information is already entered manually and you didn't do it.
You more than likely got hijacked.

karlsnooks said:

Disable your firewall.

Disable the super-duper anti software.

Disable Avast.

Now can you use a browser?

If yes, then leave all three disabled and install Microsoft Security Essentials (MSE) link in my sig.

This will enable the Microsoft security features including the Windows Firewall which is much improved over the xp and vista days.

Thank you "Maguscreed" and "karlsnooks" for your valued time spent for this post. @Maguscreed : Yet tried that already, for being hijacked, I'll to scan that too.
@kalsnook : If firewall & Avast were blocking the Internet, how could other applications, including Windows it self use the bandwidth? I've gone through the firewall settings and it's Allowed / Blocked program list as well.

My next step would be to scan for any Hijack possibilities. Even Avast & SUPERAntiSpyware returned nothing.

A Guy said:

Can you access the internet with the 64 bit IE?

A Guy

Can't say, I'm using 32 bit version of Windows 7.

That's a main office PC specs I've posted there, my problem was with Home PC with 32 bit Windows 7. Anyway, I've reinstall the OS and back on track (It would've been great if a solution was found).

Thank you everyone for their valued time and support.