I have recently experienced the 250 Error C0204 on my Konica Minolta BizHub.
This is the error name: “C0204 – Tray 2 Elevator Failure – The Lift-Up Sensor is not blocked even after the lapse of a given period of time after the lifting motion has been started.”
Here is how to fix this error:
Shut down the printer from the main button.
Start the printer while pressing the Utility / Counter button.
Press [Trouble Reset].
When you see that the display is saying “ok”, shut down the printer and start it again after around 10 seconds.
This should fix the Konica Minolta BizHub 250 Error C0204.
Let us know in the comments if it worked for you.