Help avast won't start On-Access protection

I need help. I have tried to uninstall and reinstall it several times and avast won’t activate the On-Access protection. I had to reinstall first off because I had to format my hard drive. Does anyone know what I need to do to get the On-Access protection to work? Oh and btw I’m using the home version.

Do you have any other security program? An antivirus?
Do you mean a clean install (just after the format) failed?

What happens if…

  1. Uninstall avast from Control Panel first.
  2. Boot
  3. Use Avast Uninstall for complete uninstallation (read http://www.avast.com/eng/avast_uninstall_util.html)
  4. Boot
  5. Install again by this command on the folder you’ve donwload and save the install file: setupeng.exe /forceinstall
    Where setupeng.exe is the name of the executable