Giancarlo,
I understand the situation. Don’t worry I'll help you with your issue.
I suggest you to change the firewall network profile from "Public" to "Private" and check if that fixes the issue. To change this settings, please open the AVG Internet Security and click on Menu>Settings>Components>Firewall>Customize>Network profile.
Also, please Enable all the System Rules under Menu>Settings>Components>Firewall>Customize>Policies.
I upgrade from the free AVG to AVG Protection. I use an internal messenger to communicate within the office with each other. Once I downloaded the AVG Protection the messenger is no longer allowing my the computer to see each other so we cannot send a message to each other. I need to find out to by-pass the settings of the AVG protection to allow the computers to use my network to be able to communicate with each other.
Giancarlo,
I understand the situation. Don’t worry I'll help you with your issue.
I suggest you to change the firewall network profile from "Public" to "Private" and check if that fixes the issue. To change this settings, please open the AVG Internet Security and click on Menu>Settings>Components>Firewall>Customize>Network profile.
Also, please Enable all the System Rules under Menu>Settings>Components>Firewall>Customize>Policies.