Had same problem. First it showed Error01 and after that just showed black screen when taking pictures but everything normal when displaying pictures I have made before, setting menu etc.
The I have done a full reset of the camera. Same issue.
Then I have removed the lense (haven't done this for 3 years) and voila - there it was - the closed shutter. So I have taken my iPad Pencil and have manually pushed the shutter's guides a little bet and it has clapped back to normal position. Problem solved and stays solved.