To update your Apple TV to the current software version:
1. Select Settings > General using your Apple Remote.
2. Select Update Software.
At this time your Apple TV checks to see if an update is available and a Download Now message should appear.
3. Select Download Now to start the download process.
When the update has finished downloading, an Update Now message should appear.
4. To start the update process, select Update Now. During the update process, your Apple TV will conduct a restart which is followed by the Apple logo and a status bar.
Note: On some TVs, the screen may display black for up to 15 minutes and the Apple TV may flash an amber light; this is expected behavior. Do not unplug your Apple TV during the update process.
5. After the final restart, your Apple TV plays the opening video and returns to the main menu.