I have a vintage Bernina 830 Record and walking foot. After much frustration, I finally realized that I needed to use the knee lift to raise the presser foot a little more to give enough clearance to attach the walking foot. It still takes some maneuvering to angle the walking foot, slip it on the needle bar and place the hook around the needle bar screw. Without the knee lift I couldn't get the walking foot on the machine no matter what I tried.