405 Method Not Allowed Error In WCF

I can open it up in the browser and it works, but a call from client side (using both jquery and asp.net ajax fails)

Service Contract

[OperationContract(Name = "GetTestString")]
[WebInvoke(Method = "GET",
ResponseFormat = WebMessageFormat.Json
)]
string GetTestString();

In Web.config among other bindings, I have a webHttp binding

<endpoint address="ajax" binding="webHttpBinding" contract="TestService" behaviorConfiguration="AjaxBehavior" />
EndPoint Behavior
<endpointBehaviors>
<behavior name="AjaxBehavior">
<enableWebScript/>
</behavior>
</endpointBehaviors>
</behaviors>

Svc file

<%@ ServiceHost Service="TestService" %>

Client

var serviceUrl = "http://127.0.0.1/Test.svc/ajax/";
var proxy = new ServiceProxy(serviceUrl);