Singer futura 250. while sewing the E4 code

Are you using bobbin thread? Is your thead new? Is themachine threaded correctly?

Make sure that when you thread the upper part the thread go under the circle that pull it.

Another thing is that when you hit the start button, pull the upper thread until the machine goes two or three times. It helps the bobbin thread to come up and the machine start sewing.I you leave it along the thread sometimes doesnot comes up and that is why the machine beeps.

I use this technique to make sure it doesnt beep and to cut the thread (the one at the beginning so it doesn't mess my design)