Instructions
Open the "My Xbox" menu, scroll all the way to the right, select "System Settings" then choose "Memory."
Choose the storage drive containing the Netflix application files (the hard drive if your console has one), press "Games" then scroll down the list and select the "Netflix" entry.
Choose the "Delete" option, click "Yes" to confirm the deletion, press the "Back" button until you reach the dashboard, scroll up to the "Video Marketplace" menu, choose "Netflix" then press "Confirm Download." Netflix will now be reinstalled on your Xbox 360 console, again enabling you to browse through it.