Is the Nikkor AF-S 35 mm 1.8 DX compatible with the Nikon d800?

I was under the impression that most any Nikon lens (being all F mounts) would be interchangeable between DX and FX cameras. Yet my 35mm, which was bought for a DX camera, will not attach to the d800. Though I line up the indicators, I can't twist it into place without getting some serious resistance. Attaching the same lens to my DX camera is a breeze and requires very little force. The same is happening with my Nikkor AF-S 55-200 mm 5.6 DX lens, and with my Nikkor AF-S 18-55 mm 3.5 DX lens. Are all of these incompatible with the d800 or am I missing something obvious?

Never mind. I got it. You have to push the lens slightly down into the mount and then twist.

Be glad the lens didn't mount. If it did and you took a shot, the reflex mirror would have bumped onto the protruding rear end of the DX lens and that would be an expensive repair job.

Nikon DX cameras can use either DX or FX lenses while FX cameras can only use FX lenses. It's the same with the other brands.

They are supposed to fit. With Nikon the FX camera is supposed to be smart enough that by default it should only use a cropped portion of its sensor. There should be a setting to allow it to use the whole sensor, capturing images with dark corners with the DX lenses.

The risk of damage to the mirror is something that would happen if EF-S lenses were used in full frame Canon cameras.