Hello,
maybe you guys have same problem with me when trying to build ardupilot with arduino following these instructions : http://dev.ardupilot.com/wiki/building-the-code/building-ardupilot-with-arduino-windows/
the problem occurs in step 6, when arduino IDE can't find arducopter, rover, etc..only libraries and tools. maybe you can download release version branch AP 3.2.1, unzip it to C:\GIT, then change the arduino preferences. you can download it here : https://github.com/diydrones/ardupilot/releases/tag/ArduPlane-3.2.1
thanks to you guys,
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