Dear Henry, If you are using UBUNTU Linux, together with its new Desktop Manager style called Unity: https://unity.ubuntu.com/about/ https://unity.ubuntu.com/projects/unity/ You could encounter the following error message when quiting IDL Workbench before closing the system terminal prompt: "Trying to remove a child that doesn't believe we're it's parent." Solution The solution is to define the following system environment variable: export UBUNTU_MENUPROXY=0 Now, IDL Workbench will exit without showing the above error message. Will that help? Cheers, Fernando