Instructions
Power on the Xbox 360, then navigate to the "My Xbox" menu of the Xbox dashboard.
Highlight "System Settings" within the "My Xbox" menu and press "A" on the game controller.
Highlight the "Memory" menu option and press "A" on the game controller.
Press "Y" on the game controller when you are given the option to choose a memory storage device.
Highlight "Clear System Cache" and press "A" on the game controller. Confirm that you want to delete the system cache. This will remove all previously installed game patches.