You may try to upgrade your AVG Free Antivirus only to find out that a critical error stops the installation.

AVG announces error code 0xC0070643, General internal error, with an additional message that MSI Engine failed to install the product (@AVGMSI_Error27046, driver installation failed, error 0xC0070430).

The same message suggests that you go online to learn more, but you are not directed to an error specific page helping to solve the problem. Yet, most probably there isn’t any incompatibility issue at all between AVG and Windows, you just forgot to disable other antivirus, antispyware or firewall applications you may use.

In my case I needed to disable Comodo firewall, and after that AVG finished its setup gracefully! Don’t forget also to run AVG setup as administrator: do not double click on the setup file you downloaded from the internet, but right click on it and select the command “Run as administrator”.