Possible solution everyone!?? My wife found what I suspect is the same issue on her laptop when she tried to open New Outlook yesterday 10th Feb. I've discovered that Norton 360 was, suddenly, blocking access to the internet, for both New Outlook and for Edge. What I think must have happened is that Microsoft made changes to Outlook and Edge that caused NAV to identify them both as completely new Apps - for which it was set to block access! I tweaked the network protection settings in NAV and hey presto everything's working fine again. So, may be worth a look at your Protection settings and I very much hope this helps you.
regards
geezer