i am sorry i do not know alot about java like i know how to code the information in my game to get what i want but i do not know evan what a command window is i am sorry if you can teamveiwer me and show me that would be perfect if possible.
A command window / command prompt would be your operating system's command-line interpreter, for instance on Windows it would be cmd.exe, and on a unix system it would be one of the shells e.g. bourne, bash etc.
Give the path in the error message, I would say you're running a windows system, so just open cmd.exe (Start button -> Run... -> cmd), and try running the .jar file with the java command (use the -jar flag).
Welcome to Javaranch, by the way
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