Internet Access Control in school context not working

[maddaluno]

We had successfully configured Veyon to be used in our school laboratories as support in teaching in our digital learning environments.
Now we wanted to try the "Internet Access Control" addon to block/unblock the network when needed (for example during exams).

I have installed the addon both on client side and server side but the problem that we are experiencing is that the feature is not working.
I mean, I click on the "Block Network" (that in trial mode should last just 1 minute) but nothing happens and the clients can still navigate.

Let me know if you can give me some advices about that.
Probably I missed something in the configuration (I just followed these basic configuration setup: https://docs.veyon.io/it/latest/addons/internet-access-control.html).

[tobydox]

A typical mistake is that Veyon add-ons are not installed on student computers. Also make sure to configure the Internet access blocking mechanism client-side. Is the Windows Firewall enabled on student computers? If not, please enable it and don't set any group policy which prevents applications from changing the firewall configuration.