My signalR connection is established but can not invoke the hub function.

[SFareedi]

After establishing the signalR hub connection, when i try to invoke the Hub function as following

domElement.btnConnect.click(function () {
objHub.server.adminConnect();
});

I got the following error.

There was an error invoking Hub method 'signalrhub.AdminConnect'.
at Object.error (jquery.signalR-2.2.2.min.js:9)
at init.l (jquery.signalR-2.2.2.min.js:9)
at t.fn.init. (jquery.signalR-2.2.2.min.js:9)
at t.fn.init. (jquery.signalR-2.2.2.min.js:9)
at t.fn.init.dispatch (jquery-1.10.2.js:5109)
at t.fn.init.elemData.handle (jquery-1.10.2.js:4780)
at Object.trigger (jquery-1.10.2.js:5021)
at init.triggerHandler (jquery-1.10.2.js:5711)
at Object.triggerReceived (jquery.signalR-2.2.2.min.js:9)
at WebSocket.e.socket.e.socket.onmessage (jquery.signalR-2.2.2.min.js:9)