Try removing the hard drive and boot up without it.
If that does not work try this with the HDD connected, clear all installed game updates and console cache.
Clear All Installed Game Updates and Console Cache1. Go to the "system" blade
2. Select "memory"
3. Press Y on the HD symbol
4. Press X,X, Left Bumper, Right Bumper, X,X
5. A message will appear saying: "Do you want to perform maintenance on your Xbox 360 storage devices?"
6. Select Yes
Clear Any Failed system updates that cause the console to error.1. With the console off, press and hold the sync up button
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.
Hope this helps......! (IMG:
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