Cant keep settings

Have FSX with acceleration, after i have set all the settings for the controsl ,and pressed OK I go back to the aircraft, and just like majicthe settings are all gone, throttles everthing all settings gone, I have reset and reset the settings 5 or 6 times, and yes I have calibrated each time, still they are lost, I have a 64 bit windows 7 computer, prior to this computer I had a 32 bit vista and everything seemed to run smooth, most of the time? Any help would be greatful.