Telestream released Flip4Mac WMV Player 2.1.3.3 beta. Flip4Mac enables QuickTime to play Windows Media Video (WMV).
According to Telestream, version 2.1.3.3,
Fixed issue with failed exports after installing QuickTime 7.2
If you are using QuickTime 7.2, you are recommended to upgrade to Flip4Mac WMV Player 2.1.3.3 beta (with the opportunity to register any bug reports). I don’t expect you to be very busy.