After uninstalling and re-booting, nothing was detected, and Device Manager is showing no errors.
I looked through all my BIOS settings, and saw nothing about serial connectors (nor can I recall seeing or using such connectors, AFAIK they are all USB). My System Information does not show any serial or parallel ports as installed. My infrared TV remote still works.
If anything turns up disabled, I'll post back. Until then, it's just an oddity, I guess.
Much obliged for the advice.