so what I'm trying to do is pass a simple string variable that contains my error message in C# into my javascript function when I call the function. My function call works fine, but it keeps outputting the wrong thing. This might be important too, I'm calling the Response.Write pieces within my Global.asax.cs file and my javascript file is within my Scripts folder in my MVC project. Based on the research I've found, this is what I currently have after help from the comments:

function KickOutUnwantedUsers(aMesssage) {
    console.log("Inside KickOutUnwantedUsers"); //for debugging
    console.log(aMesssage);                     //for debugging

    alert(aMessage);
    window.open('', '_self').close();
}

It just continues to output this

 <%=errorMessage%>

I'm not sure how to fix it, as everything I've found says to pass the variable that way, but I'm wondering if I need to pass it as an actual parameter into the function, and if so, how to do that.

UPDATE: Here is the C# code:

 else
            {

                string user = s.Remove(0, 4);

                string errorMessage = "THE FOLLOWING ERRORS MIGHT HAVE OCCURRED: " + user +
                    " has either been disabled or the account does not exist." +
                    " PLEASE CONTACT YOUR ADMINISTRATOR. ";

                Response.Write("<script type=\"text/javascript\" src=\"Scripts/HelpfulFunctions.js\">");
                Response.Write("</script>");
                Response.Write("<script type=\"text/javascript\">");
                Response.Write("KickOutUnwantedUsers('" + errorMessage + "');");
                Response.Write("</script>");

            }

SOLVED
@Igor was very helpful in the comments, and I did things as he suggested, which for some reason would not work at first, but then the following day I deletedmy JavaScript file, remade it under the same name and retyped out the javascript code and it worked. Coding is strange sometimes. I must've had a typo or something.

This is what the (badly documented) HttpUtility.JavaScriptStringEncode is for:

// the second argument "true" causes quotation marks to be inserted as well
var message = <%= HttpUtility.JavaScriptStringEncode(errorMessage, true) %>;

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