The following will help if you didn't properly remove a previously installed third party Antivirus program.
How to Successfully Install Avast -> http://goo.gl/VLXde
Thanks for your advices. Just want to add a few things.
I don’t and I didn’t have any antivirus software. I was trying to use the latest release which I downloaded following the link after purchasing the license. It’s not a free version.
I do have issues with firewall and it’s a standard Win10 firewall. Avast is messing with it and the there is no internet connection when avast takes the control, I mean when it’s installed. Should I deactivate standard firewall somehow when I install Avast premium security ?