Internet explorer down!

Hello, everyone! ;D
I’ve just installed a free Avast! 4 Home edition, but after that, Internet Explorer won’t work (it appears the blank page showing the message of a DNS error). Every other program works correctly.
I’ve checked the LAN conn settings of the IE, but they are correct (I usually use them in auto mode, as requested by my router).
If turn off the Avast protection… IE backs to work without problems! What’s wrong then???
Is there any setup I should do to fix this problem?
Thanks a lot in advance!
Marco

Seems like you have a firewall which is preventing avast! executables from network access…?

Make sure web shield has access through your fire wall.

Into the firewall settings, the following programs should be allowed to connect:

C:\Program Files\Alwil Software\Avast4\ashWebSv.exe (avast! Web Scanner)
C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe (avast! e-Mail Scanner Service)
C:\Program Files\Alwil Software\Avast4\Setup\avast.setup (avast! Update executable). This is a temporary file that just appears when an update (check) is about to launch, and disappears again afterwards.

Don’t need rights to connect:
C:\Program Files\Alwil Software\Avast4\ashServ.exe (avast! antivirus service)
C:\Program Files\Alwil Software\Avast4\ashUpdSv.exe (avast! Update Service)