Did you check the bobbin and/or is the top thread caught on the spool spindle?

Have you tried to remove the embroidery unit and seen if it does any stitching then? If it does not chances are it IS something like caught threads.

Ives welcome to the cute fmly, u've already gotten 2 excellent answers. I know nothing of the designer machines but if u take it apart blow or clean it out well, change needles, bobbins & thread. If it does reg. sewing, detach the embroidery unit & try to just sew some straight stitches. If none of this helps someone with a designer machine should b along & can maybe add some more things for u to try. *

Did you remove the hoop and recalibrate the emb unit before you tried again? I don't leave my unit on when I am doing plain sewing, just when I am embroidering. I do have an SE and a Diamond. BUT if it doesn't work to clean the bobbin area, rethread the machine & recalibrate the unit...you need to take it in to the repairman! I don't think any of us can help beyond that!

I have the SE and when something like this does happen, I turn everything off, and completely re thread. Make sure the bobbin casing is clean. Too, make sure that you remove the hoop and recalibrate. Don't do it with the hoop on it. Good luck, and hope you can get it up and running.

Did you get a message on your screen? Sounds like maybe you need to call your dealer for help. Hopefully you joted down what number of stitch and color you were on to start again if the recalabration works.