From what I've read about 'MC data error', it usually happens after a crash or some sort of knock, but mine has been there from the start, and I've run out of ideas for solving it. As well as 'MC data error', I get 'data recording errors'. I've tried calibrating the IMU and the gimbal. I've tried switching the micro-SD card for another one. I've tried formatting the card the way you should, when it's in the copter. I've tried clearing the image cache. One thing people say you should try is clearing the data recorder, or reformatting the data recorder micro-SD, but I can't figure out how to do this - the only control I can find in the Go App to do with the data recorder is 'enter flight recorder mode', and that doesn't help. A couple of threads say that there's a separate micro-SD card for the flight recorder, and that it's in the battery compartment, but I certainly can't see one in mine. The copter does fly, but I'm frightened to fly it more than a few yards away in case this 'MC data error' causes it to do something unpredictable. I'm out of ideas here, and I hate the idea of sending it off for repair when this problem has been here from the beginning. Does anyone have any ideas? Thanks.