If the online update continues to fail, you can manually install it via USB:
: Ensure you have at least 190 MB (or 256 MB in Japan) of free space. How to fix a xbox360 software update failed
Go to product viewer dialog for this item. software update that has failed, start by or rolling back failed updates to remove corrupted temporary files . If the error persists, you can perform an offline update using a USB flash drive. Direct Console Fixes If the online update continues to fail, you
: The second set of four digits in your error code (e.g., 4476 ) is a hexadecimal value representing the required dashboard version (e.g., 17526 ). If the error persists, you can perform an
: Go to Settings > System > Storage . Enter the sequence X, LB, RB, X, LB, RB, X . This triggers a prompt to delete all installed system updates and restart the console to try again.