Cannot enable AVG Web Tuneup

AVG Protection
1

I see the message, "Plugin is disabled in your default web browser: Mozilla Firefox. Enable the plugin."

I am using the most recent version of Firefox 50.1.0.

I cannot enable the plugin

2

Hello David,

We are sorry for the inconvenience caused.
We request you to check on the control panel "Uninstall program" list whether AVG Web TuneUp is listed.
If it is listed please uninstall it and then restart your computer once.
Once it is done, please open the AVG Zen interface and click on Web TuneUp circle and wait for few minutes and check whether it is getting installed and activated.