Is Canon EOS 400D and Tamron SP AF 17-50mm f/2,8 XR Di-II LD IF (motorized) compatible?

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

Buy	Canon EOS 400D Released: 2006 Type: Digital SLR Sensor: APS-C (1.6x) 10,1 Megapixels 3888 x 2592 pixels
Buy	Tamron SP AF 17-50mm f/2,8 XR Di-II LD IF (motorized) Released: 2008 Normal Lens (zoom) Suited for cameras with APS-C sensors Focal Length: 17-50 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

Unfortunately this Tamron lens has not been made with a Canon mount, which is needed to let Canon camera owners use a Tamron lens with their cameras.