Why can't I see the GUI of a service-started executable, and how can I fix it with psexec?

Services run in session 0, which is isolated from the interactive user session (session 1). Therefore, GUI windows (like `calc.exe`) are not visible. You can use `psexec -i 1` to launch the process in the user's session, making the interface visible. This tip is covered in the article alongside the C# service template.