... Handles Run Process Explorer, and make sure the lower pane is enabled and configured to show open handles. (Click on View, Lower Pane View, and then Handles). Then open a command prompt and ... Here’s how: 1. Launch Windows Media Player and Process Explorer, and then view the handle table (by clicking View, Lower Pane View, and then Handles). You should see a handle containing CheckForOtherInstanceMutex. ... device names into Windows internal device names. In Windows, a user refers to hard disk drives using the names C:, D:, and so on and serial ports as COM1, COM2, and so on. The Windows subsystem...