Windows 8.1 WMP no longer playing .tivo files

I recently updated from Windows 8, to 8.1. My .tivo files no longer play on WMP (there was a problem playing, etc, etc) I have the full version of Tivo desktop. I installed 'Windows 8 Codecs Pack' with no luck. I updated my VLC player, won't play on it either. Everything transfers fine..just can't play them back on my PC (Dell XPS 8700)

Thanks in advance