<p>I'm just in the process of upgrading my Preview 5 application to Beta 1, and I'm nearly there save for this one error when trying to render a control:</p>

<blockquote>
  <p>'System.Web.Mvc.HtmlHelper' does not
  contain a definition for
  'RenderPartial' and no extension
  method 'RenderPartial' accepting a
  first argument of type
  'System.Web.Mvc.HtmlHelper' could be
  found (are you missing a using
  directive or an assembly reference?)</p>
</blockquote>

<p>My markup (in the .aspx View Content Page) is:</p>

<pre><code>&lt;% Html.RenderPartial("Controls/UserForm", ViewData); %&gt;
</code></pre>

<p>I've tried using Microsoft.Web.Mvc but to no avail.  Does anyone know where Html.RenderPartial has gone, or what alternative I could use?</p>

Now fixed - the conflict was a difference in Web.config requirements between Preview 5 and Beta 1.  The following needs to be added into the system.web compilation assemblies node:
```
```
<add assembly="System.Web.Mvc, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
```
```
After this change, all of my old HtmlHelper methods magically came back!