Hi Marty,
What a very sad first post.
Is anything plugged into your Netduino? Is it a Netduino or Netduino Plus?
Also, if you plug in your Netduino into your PC via USB--do the LEDs come on? Do they stay bright?
If nothing is plugged into the Netduino, it's getting good power, and the LEDs dim after boot--then I'm pretty sure your Netduino has been damaged somehow. How long have you had it?
BTW, welcome to the Netduino community Marty.
Chris
( I have a similar problem. I got my netduino plus two days ago. (I had time to blink the onboard led last night) and now it doesn't work anymore. I tried everything I read on this post but nothing. As soon as I plug the usb on the bord I have three leds on (power - white, led - blue and ACT green) and they remain like that no matter what. I connected the 3.3V pin with the reset pad but nothing. My computer says Unknown USB device. I just got it and I didn't even have time to really play with it was in plan for the weekend). Please maybe you can give me some ideas what I can do!