The installation download goes nowhere -- I can't install Bitdefender

I've purchased Bitdefender Family Pack to renew my subscription, but I can't install it on my own PC, much less my family's devices. From Bitdefender Central's "My Subscriptions," I click on the installation link and a download file appears. When I open the download file, Windows asks if I want to allow Bitdefender to make changes to my system, I say Yes, and then... nothing. Bitdefender appears to be working on it, but it never brings up further on-screen installation instructions. When I log into the Bitdefender program to try it from the dashboard, it gives me no indication that I've renewed. (Again, I have, as shown on Bitdefender Central's My Subscriptions page. I just can't install it.) What am I doing wrong?