I am using Gradle to build my Java projects. This works well on a Mac, but the build process fails on a Windows machine, when the task clean is going to be executed.

Task :clean FAILED
FAILURE: Build failed with an exception.
What went wrong:
Execution failed for task ':clean'.
Unable to delete file: C:\0.GIT\travelerrules-dots\de.midpoints.travelerrules.dots\build\unpuzzle_temp\maven-ant-tasks-2.1.4-SNAPSHOT

The jar file is build when I omit the clean task, but I always wanted the build process to to all the build steps on Windows and on the Mac. I never found a good solution, and also upgrading Gradle did not solve the problem.

Today, I found at least a workaround. Run the following command from the Windows command prompt.

TASKKILL /F /IM java.exe

now you can use

gradle cleanEclipse eclipse clean build

without any issues.