Drawingtools won´t work

I´ve just bought Animate and I´m trying to learn, But I must have done something without knowing what, because when I try to draw all I get is the cursor with a no-parking sign under it, when moved unto the drawing. Doesn´t matter which tool I choose. How do I get rid of that?

make sure you are drawing in a cell in a drawing layer, not in a layer with symbols, and you use the right drawing tools (pen or pencil).
do you try to draw in the drawing window or in the camera view?

Thank you Rob, problem solved! I draw in the camera view. Need to read more obviously.