A night of good captures of M31 led to not being able to do calibration frames in the morning without getting "Exposure Failure" every time. I then tried a few simple light exposures in every mode, from .001 ro 10 sec and every time it stops and shows "Exposure Failure." Swapping out the cam for another (2600MM) fixes it. I tried: replacing cables, power supply, rebooting everything, installing the old factory firmware then the latest again, shooting with lens cover on and then off. Nothing. Dim exposures so the sensor wasn't uniformly saturated. I brought it in house and let it sit for 24 hours. I tried the MAC version instead of the ASIAIR, too but both still only say "Exposure Failure". I reported to ZWO through the ASIAIR app and uploaded the LOG. And I opened a request via the ZWO website.
Anyone have this problem and solve it (please read all the things I tried that didn't work).