I see somebody else was having the same problem here...
viewtopic.php?f=22&t=141207&p=785401&hilit=dongle+driver#p785401
...the problem is, I'm using the latest installer (17.3.1). Any ideas?
Fusion had never been installed on this desktop computer before, so I'm wondering if I should try an earlier installer. Maybe whatever is currently running on my laptop will be a good test.