title: Azure functions: Cannot bind parameter '_return' to type HttpResponseMessage
body: <p>I created basic Azure function from the <a href="https://azure.microsoft.com/en-us/documentation/articles/functions-create-first-azure-function/" rel="nofollow noreferrer">quickstart guide</a>. In accordance with tutorial, this default function should work instantly, but I get an error.</p>
  
  <p><strong>Function body:</strong></p>
  
  <pre><code>using System.Net;
  
  public static async Task&lt;HttpResponseMessage&gt; Run(HttpRequestMessage req, TraceWriter log)
  {
      log.Info("C# HTTP trigger function processed a request.");
  
      // parse query parameter
      string name = req.GetQueryNameValuePairs()
          .FirstOrDefault(q =&gt; string.Compare(q.Key, "name", true) == 0)
          .Value;
  
      // Get request body
      dynamic data = await req.Content.ReadAsAsync&lt;object&gt;();
  
      // Set name to query string or body data
      name = name ?? data?.name;
  
      return name == null
          ? req.CreateResponse(HttpStatusCode.BadRequest, "Please pass a name on the query string or in the request body")
          : req.CreateResponse(HttpStatusCode.OK, "Hello " + name);
  }
  </code></pre>
  
  <p><strong>Error message:</strong></p>
  
  <blockquote>
    <p>Function ($HttpTriggerCSharp1) Error: Microsoft.Azure.WebJobs.Host: Error indexing method 'Functions.HttpTriggerCSharp1'. Microsoft.Azure.WebJobs.Host: Cannot bind parameter '_return' to type HttpResponseMessage&amp;. Make sure the parameter Type is supported by the binding. If you're using binding extensions (e.g. ServiceBus, Timers, etc.) make sure you've called the registration method for the extension(s) in your startup code (e.g. config.UseServiceBus(), config.UseTimers(), etc.).</p>
  </blockquote>