I have the 8.0 version. How do I upgrade to 9.0 without crashing my system?
if you have the complete version you may uninstall the 8.0 and install 9.0
AVG 9.0 is no longer available on the official web page because nowadays AVG reaches to version 2014.0.4577. Uninstall your current AVG product using the AVG Remover and download and install the latest version from the official website.