I was playing around with ASP.NET SignalR and while trying to use Hubs, stumbled upon this error. Much as I would know that I was doing all the wrong things, I could recognize it has something to do with the line I had to embed in script <script src="/signalr/hubs"><... When I added the above line, I was wondering where does this reference come from. I assumed this must be one of the script bundling techniques of ASP.NET that would be resolved in the runtime from server. However, ......