I recently purchased a htc desire s and have been quite happy with it. I recently bought a sandisk 32gb micro-sd card to store all my media from iTunes. All my music transferred fine but when I try to play my movies (in mp4 format) an error message appears saying 'Sorry, this video cannot be played'. I have tried many different players and the same always happens. Any help would be appreciated. P.S. I checked on play store and flash player has not got any available updates.