Error: cannot return non-void from void function

[Suliman via Digitalmars-d-learn]

> ah, that's it! as spec says, D determines function return value 
> from
> the first 'return' statement it seen. in your case this is 
> `return;`,
> so function return type is determined to be `void`.
>
> if you doing `auto` functions, try to arrange your code so the 
> first
> `return` returning the actual value.
>
> besides, your code is wrong anyway, 'cause you can't have 
> function that
> returns both "nothing" and "something". your first `return;` 
> should
> either return something, or must be changed to throwing some 
> exception.

How I can terminate program? First return I used to terminate app 
if config file is exists.