We have an old LC480 and in the last week or so it has twice aborted a run by simply ejecting the plate. The program is a template that has been used many times. The xenon lamp electrical unit itself is about a year old, with the bulb replaced at the same time and we have no sign of warnings there. The machine is over 10 years old. It cut out around cycle 20 in one run, and just before the melt curve in the other run. The error we get is to check multiwell plate/block/cover configuration, which isn't even in the manual. The error code starts with 1, suggesting it's software, but I think the error is in response to the plate being ejected and the program can't do what it's trying to do - determine melt curve or continue to run amplification - but not getting at the source of the issue, which is that the plate is ejecting. Why is the plate ejecting??? Has anyone ever dealt with this?