This message indicates an unknown disk or other media error has been detected. Perform the following steps before reporting this problem:
Power off the system and make sure the relevant devices are powered off as well.
Check cables, connections, and termination. Refer to your Owners Guide.
Power everything back up and reboot your machine.
If the problem continues, replace the media.
If the problem persists, contact your System Administrator or your service provider.
For information on how to configure or disable System Alerts, click here.