It is most likely the presser foot you are trying to install was not made for your machine. There are so many machines available and most of those machines have their own presser feet, which are not interchangeable. Unfortunately, even a Singer presser foot is not interchangeable with other Singers. Some have screw attachments, others have lever attachments, some have long shanks, others have short, some are straight, others are slanted. You need to figure out what style presser foot your machine takes and then search for either the presser feet that fit or a shank adapter that you can then use snap-on feet (kits are available on eBay).

http://www.sewingpartsonline.com/sewing-machine-presser-feet.aspx

Sewing Machine Feet eBay

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