I have a nikon dx40. just bought a 650-1300 non cpu lens. is there any way to use the auto features of the camera when using the non-cpu lens? or do i have to use all manual controls?

This is usually a lens issue. If the lens is not properly attached or the lens is a non-cpu lens it shows this error. If you are using an older non-cpu, you have to switch to M-mode to use it.

Hi mmarushack, in the manual page 132 it states that the F- - error means the lens is not attached or a non CPU lens is attached. If a older non CPU lens is attached select M mode. That would be on the right side of the lens mount as you face the front of the camera. The assumption is you have a CPU lens then I would suggest doing a reset of the camera. Open the terminal rubber flap on the left side of the camera. Just below the USB connector is a small push button. That resets the camera thus fixes you camera. If not do call Nikon at 800-645-6689

Try cleaning the contacts on the lens and camera with a lint-free cloth and IPA

Remove lens, clean contacts, reattach lens, wiggle it some to seat contacts.

This is normal if you're using a non-CPU lens -- you'll have to shoot in Manual (M) mode.

If it is a CPU lens, try cleaning the contacts and reattaching. Give it a little wriggle to make sure the contacts are engaged.

Go to the support section of the Nikon website to download available firmware updates.

Have you taken the lens off to try to empty the piece that is rattling?

They will fit but will work only in manual mode

http://www.ebookspdf.com/gadget/1193/the-nikon-guide-to-digital-photography-with-the-coolpix-l5/

Click the orange download button

you call the computer expert to your home and then tell him this thing. he will give you the full idea about it. from my side it is the camera body.