problem with the firewall

I downloaded the Avast free antivirus about a month ago. Two weeks ago, I was offered a free trial of 30 days of Avast Internet security. But the firewall is not actvated. When I click on “Rétablir” (ie the french for “correct/relaunch” ) and… nothing happens ! What can I do?
Thanks for helping…

Repair avast:

  1. Control Panel - Add/Remove programs - avast!
  2. Scroll down and click on ‘Repair’.
  3. Follow instructions.

Sorry, don’t know the French terms…

@ delphhumb
When you had the avast free version, which doesn’t have a firewall, presumably you had a firewall.

What was this firewall and did you uninstall it (before installing Avast Internet security) ?