from stardock.......FAQ
My min/max/close buttons have stopped working . . .
What has happened is that something is preventing WindowBlinds from getting the mouse messages. The most common cause of this is an accessory called CommonName that steals the mouse messages for it's own nefarious purposes and doesn't pass them on to WindowBlinds. To restore your button function, you must remove CommonName from Add/Remove Programs. There are other utilities that can cause this problem, like FileBox Extender or Logitech Immersion Desktop – the latter example can be fixed by using the “Disable forces†option, but some are simply incompatible with WB.
Maybe that will help you