Avast not starting up. (Free)

So I just downloaded the free version of Avast, hearing from friends that its a good free antivirus. I installed it, and everything went perfect. It asked me to restart, so I restarted. After comp came back on, Avast seemed to turn itself off. It’s telling me that it has been stopped, or in a inconsistent state. It gives me a button to restart the program, but every time I click it, it gives me the waiting cursor, and than nothing happens. Help me please.

I suggest an installation from scratch:

  1. Download the latest version of avast! Uninstall Utility and save it.
  2. Download the latest avast! version and save it.
  3. Uninstall avast from Control Panel (if possible). If, for any reason, you can’t run it, try booting in Safe Mode and doing it from there. Anyway, boot after that.
  4. Run the avast! Uninstall Utility saved on 1. If, for any reason, you can’t run it, try booting in Safe Mode and doing it from there. Anyway, boot after you’ve run it.
  5. Install avast! using the setup saved on 2. Boot.
  6. Register your free copy or add the license key for Pro.
  7. Check and post the results.

Which was your old antivirus (before avast)? How did you uninstall it?