I do notice that, if I try to open WMV Player, it says"QuickTime Player must be installed to run this application" - even though QuickTime Player is on my drive.
The normal fix for that is to reinstall Flip4Mac (WMV Player is a component). In the latest version, Flip4Mac 3.0, it is called
Flip Player. You can access the free upgrade through the Flip4Mac pane in System Preferences. (If you had Flip4Mac Pro installed the upgrade costs $9.00.