This is a bug in some versions of the Arduino IDE. Try updating to the version 1.6.12 or further.
Don't give up yet. Our experts can help. Paste your full stack trace to get a solution.
java.io.IOException: Cannot run program "sh" (in directory "C:\Jenkins"): CreateProcess error=2, The system cannot find the file specified
at java.lang.ProcessBuilder.start(Unknown Source)
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