CORS will need to be configured for the external system implemented web service to allow autoVHC to access / call the methods.

For a .NET ASMX WebService add the following to web.config:

<httpProtocol>
  <customHeaders>
    <add name="Access-Control-Allow-Origin" value="*" />
    <add name="Access-Control-Allow-Headers" value="Content-Type" />
    <add name="Access-Control-Allow-Methods" value="GET, POST, PUT, DELETE, OPTIONS" />
  </customHeaders>
</httpProtocol>


If you have some additional HEADER parameters, you need to add them to Access-Control-Allow-Headers, like:

<add name="Access-Control-Allow-Headers" value="Content-Type, X-Your-Extra-Header-Key" />


And finally, to handle OPTIONS requests you must reply with empty response, adding in your application class:

protected void Application_BeginRequest()
{
    if (Request.Headers.AllKeys.Contains("Origin") && Request.HttpMethod == "OPTIONS")
    {
        Response.Flush();
    }
}

For more information on CORS see: