Interesting to hear that chrome was knowcked out - it happened to Firefox as well and all indications are that this is a Norton issue. I also had Adobe Creative Cloud become unresponsive and after two hours with their support they cited clashes with Norton. Eventually sorted by closing the firewall for a while.
I now have the problem that Norton itself won't launch and it has been struggling to do so for weeks - starting sometime and not others. I now have no way of knowing if it is actually working. I have got Win 10 so I have made sure that Windows defender is up to date and have cancelled my Norton subscription which was due to renew soon.