Unable to turn on a firewall

I recently purchased Avast internet security and since i have downloaded it, i have not been able to turn on the firewall. every time i try it says “Unable to start a firewall.” Also every few minutes an avast message pops up saying threat has been detected and i believe that is because the firewall is off. can anybody help me and tell me how to turn on the firewall and fix my problems? thanks.

Your PC may be infected, you may want to follow these instructions : http://forum.avast.com/index.php?topic=53253.0

If you submit logs… make a thread in this board : http://forum.avast.com/index.php?board=4.0

To fix the Firewall :

  1. Download Avastclear, Rejzors uninstall tool and the appropriate Avast program edition

Note: You need to be ONLINE during this install

http://files.avast.com/iavs9x/avast_free_antivirus_setup_online.exe
http://files.avast.com/iavs9x/avast_pro_antivirus_setup_online.exe
http://files.avast.com/iavs9x/avast_internet_security_setup_online.exe
http://files.avast.com/iavs9x/avast_premier_antivirus_setup_online.exe

Avastclear : http://files.avast.com/iavs9x/avastclear.exe
Rejzors Uninstall tool: http://rejzor.wordpress.com/avast-cleanup-tool/

  1. Uninstall Avast by control panel [If you don’t have Avast in control Panel go to #4]
  2. Uninstall in safe mode using Avastclear.
  3. Run Rejzors Uninstall Utility in Normal Mode (removes traces avastclear doesn’t) - reboot.
    Check : Once uninstalled check in device manager>view>show hidden devices if there is anything related to avast with a yellow triangle… if so, uninstall it and reboot.
  4. Install the version you downloaded.
  5. Reboot.

I would wait with the fix firewall until computer is confirmed clean…it seems you have something that try to phone home
So follow the guide Alikhan gave link to and attach logs from Malwarebytes / OTL / aswMBR