Dear community, I have a problem with my autopilot(tiny v2.11), and don't know how to solve it. I have the XBee Pro 2.5 modems(2.4GHz). I have configured them with the X-CTU sofware(baud rate to 57600, firmware: coordinator AT and end device AT, and finally the two have the same Pan ID). I use the transparent protocol(paparazzi). The "downlink" is perfect. I can see the movement of my aircraft in the GCS, the battery message, GPS info, throttle, all the messages look ok....but I have no "datalink", or that's what I think. Once I've launched a modem session, I get GPS fixed and stay in "holding"...but I can't launch the aircraft, or change the mode via GCS. I have launched the "datalink messages" and can see a "WIND" message sending each 10seconds, but when I try to launch, a "BLOCK" appears in the "datalink messages", but it isn't sent(I've been waiting for more than 180seconds)...and there is no activity in the console of the GCS or in the main paparazzi center one(nothing written like an error or so). Does anybody know what may happen?May I miss anything related to my configuration settings, the software or so on? I have been looking in the devel-list for related problems, but haven't find anything that does the trick. Thanks.