LED not lighting up with Ardunino xbee Shield

Hello everyone,
Why can’t my LED light up when i am using a Arduino Xbee Shield, however it can light up when i am using a sparkfun breakout board with Breadboard. So how can my LED light up with an Arduino xbee shield? i am using a sample code which i found it online. So any suggestion would be appreciated.
THanks

That is a question you really need to ask on the Arduino forums.