If you experience the error code R3000 on your Xbox 360, it's typically caused by old Netflix information stored on your device that needs to be refreshed. Follow the troubleshooting steps below to resolve the issue.
Press the Guide button on your controller.
Select System Settings.
Highlight Memory Unit, Hard Drive, or USB Storage, then press Y on your controller.
Select Clear System Cache.
If you do not see Clear System Cache, check a different storage device.
When prompted to confirm storage device maintenance, select Yes.
Once you've successfully cleared the system cache, try Netflix again.
From the Xbox 360 Dashboard, navigate to Apps and select My Apps.
Highlight the Netflix app.
Press the X button for app details.
Press Yes to confirm.
From the Xbox 360 Dashboard, navigate to Apps.
Select Netflix to begin downloading the app.
Once the download is complete, sign back in and try Netflix again.