JavaScript error in Browser-Link

Question

I am working on a project that a former colleague has made. If I run this ASP MVC 4 application in Firefox everything works fine but, when I run it on Internet Explorer 9 I get this weird error:

It says there is a error in the SignalR JavaScript Library but I never heard of this. It breaks into a JS file that is not even in the solution.

This SignalR extension is not installed.

All the references in my views:

<script type="text/javascript" src="~/Scripts/jquery-1.7.1.min.js"></script>
<script type="text/javascript" src="~/Scripts/perso.js"></script>
<script src="../../Scripts/jquery-1.7.1.js" type="text/javascript"></script>

UPDATE

I have found the problem, in my console log it breaks on this error:

TypeError: a[0] is undefined @ browserLink:37

This occurs in my jQuery files. I have updated them with the newest version but no success.

I have no idea how to fix this, any ideas?

Answer 1

One possible reason, duplication of jQuery file. As you incldued jQuery file twice which cause conflict and jQuery stops working:

<script type="text/javascript" src="~/Scripts/jquery-1.7.1.min.js"></script>
<script type="text/javascript" src="~/Scripts/perso.js"></script>
<script src="../../Scripts/jquery-1.7.1.js" type="text/javascript"></script>

so replace it with:

<script type="text/javascript" src="~/Scripts/jquery-1.7.1.min.js"></script>
<script type="text/javascript" src="~/Scripts/perso.js"></script>

Answer 2

I imagine that you're using Visual Studio 2013? If so, there's a new feature called Browser Link, it's enabled by default. I just upgraded to VS2013 as well and I'm getting a lot of errors related to Browser Link, when I disable it everything works perfectly.

Here's some more information about Browser Link and how to disable it: http://blogs.msdn.com/b/webdev/archive/2013/06/28/browser-link-feature-in-visual-studio-preview-2013.aspx