To broadcast to Twitch from your Xbox One, the following must be true:

• In your Profile, your presence is set to "Online".
  
• In the Settings app under "Privacy and online safety", "See if you're online" is set to "Everyone" and "Broadcast gameplay" is set to "Allow".
  
• In the Settings app under "Preferences", "Allow broadcasts and Game DVR uploads" is checked.

In order to include Kinect information in your broadcast, the following must be true:

• In the Settings app under "Privacy and online safety", "Share content made using Kinect" is "Allow".
  
• In the Settings app under "Kinect", "Kinect on" is checked and to include Kinect audio in your broadcast "Use Kinect microphone for chat" is checked.

More Best Practices and Troubleshooting Tips

Network
A wired connection is better than a wireless connection.

Your Xbox Live Reputation
Your XBL account must be in good standing (i.e., not have reputation that is too low).

Privacy Settings
You must be signed in with Adult privacy settings (i.e., all settings enabled). Make sure there are no Child profiles signed in when trying to broadcast.

Twitch Stream Key
Try resetting your stream key once by going to your Dashboard - [ Register or Signin to view external links. ] - then click the Stream Key tab, then click Show Key and Reset Key...just once!

Do not reset your stream key multiple times to avoid a 15 minute lockout.

Twitch Connections
Make sure the Xbox connection exists in Settings > Connections: [ Register or Signin to view external links. ]
[ Register or Signin to view external links. ]
You may also want to come back here, mouse over the check mark and click DISCONNECT, then uninstall the app, then reinstall the app and retry the activate process by taking the code to twitch.tv/activate

Hard Reset
If your Xbox One locks up, try a hard reset: Press the power button on the front of the console for 10 seconds, then remove the power for 30 seconds and restart the console.

Uninstall and Reinstall the Twitch App
If all else fails, please try uninstalling the app and reinstalling. To uninstall the app, find the app in your Home screen, then press the menu button to open the app menu, and select Uninstall.