Vladimyr,

I don’t think you can block it and if they are going to discontinue support for 2014 then yes. As for your statement on Windows 10 I don’t think that’s the issue. I did get the Windows 10 upgrade option with a windows update but I removed it’s control files and entries and selected the “Hide Update” option on Windows update so Avast had no way to check if the OS was eligible unless it’s just checking which version your running now and is not based on that.

I also had 2014 set to “Manual” so they must be bypassing that setting and installing anyway. You can try blocking Avast’s command and control server using a firewall but then you’ll have issues with getting the virus definition updates and if they are truly not supporting any other versions then it’s kind of pointless.