Since you may have a different firmware that you want to use, I will go over changing this. Change the drop down menu on the left to XB24-ZB (for regular zigbee configuration), or XBP24-ZB for XBee pros. Change the right drop down bar to best fit your project. Click Write, and it will write the xbee with that firmware. On some of my XBees that I had to restore, it came up with the error message again. If this comes up again, connect GND to RST (not RTS) on the Explorer together with a jumper wire for about one second. This error message should go away.