ERROR: Exception in thread "main" java.lang.NoSuchMethodError: main

[barney]

Hi, I'm having a problem running .java programs in cmd prompt, its compiles ok but when i go to run it, example -->(java prac8prog1)
it brings up the following error:
"Exception in thread "main" java.lang.NoSuchMethodError: main"
Im using a JAR file ( import B102.*; ) at the top of my programs, that I was told to use, could this be whats the causing the error?

Also I need some help with a different program I have to do, I need to know how to set out a character array for the 26 letters in the alphabet. I'm pretty sure what i started doing below is wrong and i need some advice.

Code:

class Assignment2prog1
{
    public static void UserInput()
    {
        public String Data = new String()
        Screen.out.println("Please enter a series of character values from the keyboard: ");
        String.toLowerCase()
        Data=keybd.in.readchar();
        return Data;
    }

    public static void Calculate()
    {
    	private char calcArray[] = {"a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z"};
    	private int index;
        //??
        for(index=0; i<?; index++)
    }

    public static void Display()
    {

    }

    public static void Main(string args[])
    {
    	int Input=0
    	
    	Input = UserInput();
    }
}

Thanks.

[lenny]

The name of the entry point function should be main() and not Main().