Is Canon EOS Rebel XTi and Nikon AF-S 400mm f/2,8 E FL ED VR compatible?

Below you will find your chosen camera and lens. Click on the product name for more information.

Buy	Canon EOS Rebel XTi Released: 2006 Type: Digital SLR Sensor: APS-C (1.6x) 10,1 Megapixels 3888 x 2592 pixels
Buy	Nikon AF-S 400mm f/2,8 E FL ED VR Released: 2014 Telephoto Lens (prime) Focal Length: 400 mm Aperture: f/2,8

Can you combine these two?

This is the short answer:

No! This combination is not compatible

The camera and lens you have chosen cannot be combined. Here is a longer answer:

A non-Canon lens on a Canon camera

This is a Nikon lens and unfortunately they are not constructed to work with Canon cameras. If the lens would have been a Sigma, Tamron och Tokina it would perhaps be different since they are available with a compatible Canon mount.