APM 2.6 Board - XBee 900 Connection


I got stuck on a problem for days, at last I decided to ask the problem here.

I have a APM 2.6 Board, one of the XBee 900’s is connected to the board, I can connect the Mission Planner with this APM board.

But in the ground side, I opened a new Mission Planner and tried to connect the other XBee to the software, but it always gives error saying “No Heartbeat Packets Received”. Com Port and Baud Rate is set correctly.

Any solution, recomendation will be appreciated.

-All usb drivers are updated.
-I can connect these 2 XBee’s using X-CTU software, and I can transmit and receive data to and from each other.
-I tried these all of the software versions of XBee’s.