Can't start adapter when the I m connected to LAN

I created an oracle (intelligent) adapter. When I am not connected to the LAN, I could actually start up the adapter successfully… However, once I pluged in network cable. The ball will turn to red, which mean the adapter is not running anymore. I had tried to insert record into the database manually, and it works… So, means that is something wrong with my adapter… so, any advice or suggeation?