Mi error. Tiene usted razón, tu versión es 5.0 y no 5.1.
Sugiero una instalación limpia.
Puedes seguir los pasos en Inglés?
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. If, for any reason, you did not solve, try doing the step 3 in Safe Mode anyway.