Thanks to the help from some forum members, I got it running again. Apparently I'm not the only one with this issue. The trick is to unplug the unit from the power outlet (which I thought I had done, but apparently hadn't). Once the power had been disconnected for a few minutes, I plugged it in and it booted up as it had before. But this time when I did a channel search, it found all stations right away.
7/18/13 at 5:04pm