A much bigger deal was iTunes. I could not get iTunes to make a secure connection to the iTunes Music Store, thus I could not authorize my computer. This prevented me from playing any songs that either Crystal or I had bought to play. That was a very big problem. I kept a cryptic error message about "Unknown error -9808."
I ran the iTunes Network Diagnostic (I didn't even know they had this!) It took me to a support page that suggested that I needed to make sure Internet Explorer had either SSL 3.0 or TLS enabled. I found it funny that I had to fiddle with Internet Explorer to get iTunes to work. But that was not the problem.
I turned off the Windows Firewall. No luck. I tried turning down IE's security settings as low as they can go. No luck. I tried telling Vista to run iTunes as an administrator. No luck.
Finally I found this article on Apple's support discussions. This sounded like it would not help, but I tried it anyways. I reduced the Maximum Transfer Unit on my router from 1500 to 1400. I restarted the router. Then I launched iTunes. Mysteriously I got a message from Windows Firewall saying that it had been blocking some iTunes functionality.
WTF!? I had turned Windows Firewall off. I had rebooted since I had done that, and got a complaint from Windows about having it turned off. And yet, it claimed it had been interfering with iTunes. It kindly asked me if I wanted to stop blocking iTunes, and I emphatically clicked in the affirmative. I then tried once again to sign in to the iTunes Music Store and voila!
I wish I could claim to understand what happened here. Did changing the MTU on my router really cause Windows to suddenly ask me about enabling iTunes functionality? Was it just same bizarre coincidence? Who knows. At least it is working. For now.