Q: iTunes 12.3.3.17 will not play any media. Just sits there.

After a couple years without an iPhone, I picked up a 6+ and connected it to iTunes for the first time today. After removing old phone backups and syncing the new phone, none of my media will play from within iTunes (music, movies, TV episodes... nothing in any playlist or directory). Media plays fine in VLC Media Player & elsewhere, and on the phone of course, but even after uninstalling all Apple components from Windows 7 and reinstalling, the same symptom exists; the selection shows up at the top (music, movie, or podcast) but does not progress through the selection. I am stuck for next steps to fix this. Thoughts?