I assume all the coding compiles fine?
If so, then it might be a hardware issue. Check to make sure you have everything plugged in, etc (the basics).
Some things to consider:
Is the sample code made for an older version of the Arduino coding software (i.e. 0023)?
Did you update your libraries?
If anything, I would check the sample code to see if it was made with an older version, and if it was, compile and upload to try that instead.