This morning as I started up Archicad I got the following message:
Windows Security Alert
---------------------------
Windows Firewall has blocked some features of this program
Your network administrator can unblock this program for you.
...
This program has already been blocked or unblocked for a different network location.
Archicad seems to have opened up fine, but I do wonder what's being blocked, whether it matters, and why it would suddenly turn up at random when I've been using Archicad 17 with no hassles since it was issued.