unfortunalty its abit of a generic error.
i had it once on the A33, but mine was simple i just took the lens off and wiped the contacts on the lens and camera. i also took the battery out. its worked fine after that, but it could more serious.
try the above and see if it helps, also while the lens is off look and see if the Shutter is down and convering the sensor (if you can't see through the pellicule mirror there's a little spring clip at the bottom of the frame which holds the mirror press that down and it will pop up the mirror so you can see the sensor)
other then that try a fresh battery/recharge your current one, other then that its a job for the service centre
