I just now sent the log file along with an explanation of what actions were logged.
I have some additional information to provide. As I said earlier, I watch only the Verizon Clear QAM channels, which include channels 4 (NBC), 5 (Fox), 7 (ABC), 9 (CBS), and 26 (PBS). It turns out I get the signal lock problem only on Channels 5 and 7. I first discovered the problem when I was trying to tune to channel 5 and when the problem occurred I next tried channel 7. With the problem demonstrated on two different channels, I assumed incorrectly that the problem occurred for all channels.
I note that I did successfully record a Channel 5 program on 11/16, which is after the 11/12 windows update.