Configuring xBee programmatically

I have an xBee Series 2 connected to an xBee shield, which is connected to an Arduino. I do not have an xBee Explorer USB, so I cannot use X-CTU for this purpose.

I tried configuring the xBee programmatically using the code examples that came with the xBee API which send AT commands, but I keep getting a message that there is no response from the radio.

I read that this should be possible. Am I missing anything?

The series 2 or ZB product is a Zigbee mesh networking product. For it to establish a network and allow communications to occur, one of the radios must be configured with the Coordinator firmware which does require the use of XCTU.