I’ve run into many goofy situations where for whatever reason you need to launch the “Mail” control panel window from a command prompt. Maybe some IT dude years ago put in a group policy to hide it so users wouldn’t mess with it. Maybe somehow the user deleted it. Or maybe an update/install of office went very wrong.
Regardless, launching the “Mail” control panel window from a command prompt is really easy if you know the command…
control mlcfg32.cpl