with avast internet security 2015 running on windows 10, is it recommended to turn off windows firewall, or should I let both firewalls run at the same time?
I don’t know about Avast Internet Security as I have Avast Free. While doing research I found this.
https://forum.avast.com/index.php?topic=101322.0
Avast actually recommends that you leave Windows Firewall ON.
Read the 1st comment from Dch48
Beware that Windows 10 is still in development stage and still changing and software and programs such as antivirus and etc will react different from the operating system. Make sure you have the latest version of Windows 10 and Avast IS
It is not recommended to have two firewalls running and avast does not recommends that for sure. Even Windows Firewall itself warns about possible problems with two firewalls running. So use them at your own risk. You should leave Windows Firewall on only with avast Free, which does not have firewall.
Quoting a topic that is three years old isn’t wise, too many things have changed not only with avast but more so with the OS versions. So the advice is invalid.
The case now I would say you should disable the windows firewall. I don’t know if win10 would actually disable the windows firewall when another firewall is installed. This could be similar to windows disabling windows defender when a 3rd party antivirus is installed.