Xbox 360

The E71 is a Dashboard Error usually and error within the Xam.xex usually caused by an update error. Try clearing failed updates by following the instructions below:

1. With the console off, press and hold the sync up button (the small white one)
2. While holding the sync button press the power button to turn on the console
3. Continue to hold the sync button until the Console has booted up completely.
4. During the boot process the console should clear any failed updates, allowing you to use it normally.

However if this does not work there is no other solution and the Xbox must be sent back to Microsoft for repair. (Replacement)