thanks @mrutyu1987 for reporting. By the look of it it looks like the python debug libraries have not been found when you built. Can you confirm that you have a file called `_rclpy_d.pyd` in `D:\Test\ROS_Source_Build\Debug_Python\install\Lib\site-packages\rclpy` ? I would expect the result to be the same but can you try to run the executable directly: ``` call D:\Test\ROS_Source_Build\Debug_Python\install\setup.bat D:\Test\ROS_Source_Build\Debug_Python\install\Lib\demo_nodes_py\talker.exe ``` Finally can you provide your build output of rclpy and demo_nodes_py ? ``` rmdir /S D:\Test\ROS_Source_Build\Debug_Python\build\demo_nodes_py D:\Test\ROS_Source_Build\Debug_Python\build\rclpy python_d D:\Test\ROS_Source_Build\Debug_Python\src\ament\ament_tools\scripts\ament.py build --cmake-args -DCMAKE-BUILD_TYPE=Debug -- --only rclpy demo_nodes_py ``` Thanks! --- [Visit Topic](https://discourse.ros.org/t/ros2-debugmodulenotfounderror-no-module-named-rclpy--rclpy/2401/2) or reply to this email to respond. If you do not want to receive messages from ros-users please use the unsubscribe link below. If you use the one above, you will stop all of ros-users from receiving updates. ______________________________________________________________________________ ros-users mailing list ros-users@lists.ros.org http://lists.ros.org/mailman/listinfo/ros-users Unsubscribe: