You may want ot check the bobbin winder on your machine. Mine did this and the fly wheel would not turn so I thought it was thread in the tension disks. Well come to find out that after I wound the bobbin, I forgot to move the winder back in place. And also when you thread the machine make sure your presser foot is up so the thread goes inbetween the tension disks like it is supposed to. Good luck, Huggies, Fay