This lens has no electronics, no autofocus and no lens IS. As such this lens has no electronic contacts on the mount. If your camera’s setting are set to default chances are that your camera won’t take a photo when you mount this lens. There is a setting in the menu called Release Shutter Without Lens. Set it to Enabled/On and your camera will be able to shoot photos.

*If you’re shooting with a brand other than Canon you’ll find a similar setting in your menu. It may have a different name but once you enable it you’ll be able to shoot with the lens.

More information here: The One Setting You Have to Change