WMP needs "run as administrator" to run, why?

when doubled clicked mp3 files or video files which usually automatically
runs and plays on Windows media player, nothing happens, wmp wont open to
play the files. double clicking the player itself also wont work, the player
wont open. The only way to start wmp is to right click wmp and run as
administrator. i try to set wmp to run as administrator at all time by going
to properties, capability, but that was not possible as it states that wmp is
part of the windows version.
can any help me?