Hello Catherine.
Thank you for contacting AVG Support Community.
We're sorry to hear that you're facing this trouble.
We will check and help you further.
If your PC is connected to an untrusted network, some of the personal applications or connections will not work in order to protect your PC. Because hackers may get into your PC via untrusted networks. So the screen mirroring failed to work before, After that, you changed the network profile to 'I trust this network' which means AVG considered your current network as trusted one so it allowed screen mirroring.
We request you to repair AVG Internet Security and check if the network selection stays in 'I do not trust this network'.
Please refer to the below article to repair AVG Internet Security.
https://support.avg.com/SupportArticleView?urlname=repair-avg-antivirus
After repairing the program, please reboot the PC to apply the changes.
Thank you and keep us updated.
Hello Catherine.
Thank you for contacting AVG Support Community.
We're sorry to hear that you're facing this trouble.
We will check and help you further.
If your PC is connected to an untrusted network, some of the personal applications or connections will not work in order to protect your PC. Because hackers may get into your PC via untrusted networks. So the screen mirroring failed to work before, After that, you changed the network profile to 'I trust this network' which means AVG considered your current network as trusted one so it allowed screen mirroring.
We request you to repair AVG Internet Security and check if the network selection stays in 'I do not trust this network'.
Please refer to the below article to repair AVG Internet Security.
https://support.avg.com/SupportArticleView?urlname=repair-avg-antivirus
After repairing the program, please reboot the PC to apply the changes.
Thank you and keep us updated.