I bought a Bernina 730 four months ago. This weekend when I was embroidering, I kept getting an error message to check the hook system, clean bobbin, check lower thread. I thoroughly cleaned and oiled the machine, but it kept happening. It also happens in the sewing mode. I took it to my dealer yesterday, and an employee told me she had the same problem, that the technician has checked it several times, and can't find the cause. The tech told her to over ride the bobbin in the settings, and that works, but you don't get a message that the bobbin is about to run out or that the thread has broken. I think I paid too much for this machine to have to over ride something. Does any one else have this problem? Thanks.

I also have this machine. When I get this error message, I find I have left the door to the bobbin chamber open. Closing it solves the problem. Hope this helps.

I made sure the door was closed. I talked to the owner of where I got the machine, and I'm taking it back tonight. She said not to go by what someone else's machine does. Thanks for you help though.