Why are my client-side javascript breakpoints not being hit? - visual-studio-2012

Question

I'm setting forth on my first Single-Page Application. I've installed Visual Studio 2012 Professional with Update 2, and loaded the project. I've gone into IE10 and unchecked the "Disable script debugging (Internet Explorer)" checkbox.
Here's my code snippet that ought to be hit by the debugger
However, when I run the code the red breakpoint symbol turns to a hollow white one
with the legend "The breakpoint will not currently be hit; no symbols have been loaded for this document".
I'm at a loss here. Even the debugger; statement isn't causing the code to break out.
I've reinstalled VS2012 and Update 2 twice now.
Thanks
Edward

Answer 1

Do you have multipel projects in your solution, is the file where you are putting breakpoint belongs to same project that is set as start up project?

Answer 2

have you tried to give the function a name (openMain function name here)
Just to make it a bit more understandable I'll show a code that I used for a site.
<form name="myForm" action="mailto:kkatsman#rocfriesepoort.nl?subject=Stickers" enctype="text/plain" method="POST" onsubmit=" return formcheck()">
<table id="formulier">
<tr>
<td>Klas:</td> <td><input type="text" required name="klas" id="klas" onkeyup="vulaan(this)"></td>
</tr><tr>
<td>Examencode:</td> <td><input type="text" required name="examencode" id="examencode" onkeyup="vulaan(this)"></td>
</tr><tr>
<td>Examennaam:</td> <td><input type="text" required name="examennaam" id="examennaam" onkeyup="vulaan(this)"></td>
</tr><tr>
<td>Datum:</td> <td><input type="text" required name="datum" id="datum" onkeyup="vulaan(this)"></td>
<td colspan="2"></td>
<td>Week:</td> <td><input type="text" required name="week" id="week" onkeyup="vulaan(this)"></td>
</tr><tr>
<td>Tijdstip: van</td> <td><input type="text" required name="van" id="van" onkeyup="vulaan(this)"></td> <td>tot</td> <td><input type="text" required name="tot" id="tot" onkeyup="vulaan(this)"></td>
<td>Docent:</td> <td><input type="text" required name="docent" id="docent" onkeyup="vulaan(this)"></td>
</tr>
</table>
So when there is a keypressed in a certain textbox it refers to the function "vulaan"
now my javascript file looks something like:
function vulaan()
{
//voor de klas
var klas = document.getElementById('klas').value;
var klas1 = document.getElementById('klas1').value;
var klas2 = document.getElementById('klas2').value;
document.getElementById('klas1').value = klas;
document.getElementById('klas2').value = klas;
}