Question: I created a setup by Advanced Installer software for my program that I've written by c#. I installed my program on VMWare Windows7.

When I try to run it this message is displayed:

![Class not registered](https://i.stack.imgur.com/efAyh.png)

Answer: 
It would be a good idea to add a default case to your switch statement.

Example:

```
switch (monthNumber) {
    case 1: monthString = "January";
        break;

    //other cases...

    default: monthString = "Invalid Month Number";
        break;
}

```

This way if `monthNumber` is not 1-12 then there is still a default case for the switch statement to flow to.
monthString is a local variable within main(), therefore, it must be initialized to prevent the compiler error.

If monthString were a Class variable then it does not have to be initialized explicitly.

You can do this by moving monthString outside of main() and declare it as:

static String monthString;