I'm trying to validate some code via javascript. The drama I am having is that I receive an 

> 
> "Uncaught TypeError: Cannot set property 'border' of undefined". 
> 
> 
> 

I am new to javascript and trying to get a full understanding of why this happens and how to prevent this in future coding projects. My goal is if the validation fails it changes the text box border to red. 

```
function validation_Step1(event) {
    var Firstbox = document.getElementsByName("Firstbox");

    if (Firstbox.value == null || Firstbox.value == '') {
        document.getElementsByName("Firstbox")
            .style.border = "2px solid red";
        alert("Error");
        return false;
    } else {
        return true;
    }
}

```