help! can't get OM lens and adapter to work nex5n

I have a Nex5n. I purchased an OM adapter from Rainbow for my Oly zuiko OM lenses. I have 3 such lenses (50mm,35mm, and 28mm). I can't get em to work. By not work i mean the camera gives me a message 'lens not recognized-please attach lens properly". I believe the adaptor is correct as it reads OM-NEX. I believe i am installing it correctly as i line the lens red dot up with the adaptor face red dot and rotate, then line up the adaptor red dot at base to the white dot on camera and turn and it all clicks into place. Alignment seems correct as the OM-NEX text on adaptor is facing up and is aligned with center of lens (red dot), yet the camera does not let me take photos, only gives me the message i stated earlier. I've tried all three lenses and also P,S and A modes with no luck. What am i missing or do i have a defective adaptor?
thank you!
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Dan Schlender