The following information is from Microsoft's Extender Readme file which is buried in C:\Windows\ehome\ 

MEDIA CENTER EXTENDER TOOLS
Three tools are available for you to maintain the Media Center Extender and monitor its performance. These tools are installed on the Media Center PC.

Media Center Extender Manager:
Use the Media Center Extender Manager to add another Media Center Extender to your Media Center PC, or update the software for the Media Center Extender.

To use the Media Center Extender Manager, go to the Media Center PC and on the Start menu, point to All Programs, point to Accessories, point to Media Center, and then click Media Center Extender Manager.

Important!  You should only update the Media Center Extender if you are absolutely sure you should do so. To determine if you need an update, contact your hardware manufacturer for more information.

Media Center Extender Network Performance Tuner:
The Media Center Extender Network Performance Tuner tests how well your network supports the Media Center Extender. If you have problems receiving video information such as Live TV or Recorded TV on the Media Center Extender, use the Network Performance Tuner to determine the strength of the network signal and capacity. In addition, the Network Performance Tuner provides information about how to improve network performance between the Media Center Extender and the Media Center PC.

To use the Media Center Extender Network Performance Tuner, go to the Media Center PC and on the Start menu, point to All Programs, point to Accessories, point to Media Center, and then click Media Center Extender Network Performance Tuner.

Media Center Extender Resource Monitor:
To quickly see the status of system sources in use by the Media Center Extender, use the Extender Resource Monitor. This tool shows you the status of four important PC resources: CPU Use, Disk Usage, Network Usage, and Memory Available. For more information, refer to the Media Center Extender User's Guide.

To use the Extender Resource Monitor,go to the Media Center PC and in the notifications area right-click the Extender Resource Monitor icon. Then select Show System Resources.

POWER LIGHT
On the front of the Extender, the power light shows the current status of the Extender.
If the light is -

Solid green:
The Media Center Extender is starting up and operating normally.

Fast blinking green:
The Media Center Extender software is updating.

Fast blinking yellow or fast blinking blue:
The Media Center Extender is resetting.

Fast blinking red:
A system failure has occurred.

Slow blinking green (on/off):
The Media Center Extender is in Test mode.

STARTUP ERROR CODES
The Media Center Extender might display an error code on screen during startup which includes a number within a triangle.

If the number is a 1, 2, or 3:
Contact your hardware manufacturer for assistance. For more information, refer to the Media Center Extender User's Guide.

If the number is a 4:
Make sure the Ethernet cable connected to your Media Center Extender is properly installed or replace the Ethernet cable with another one.

For more information about these error codes, refer to the Media Center Extender User's Guide.

MORE HELP
For additional troubleshooting information, go to the Media Center PC and on the Start menu, point to All Programs, point to Accessories, point to Media Center, and then click Media Center Extender Help.