title: CS1928: 'System.Web.Mvc.HtmlHelper' does not contain a definition for 'DropDownListFor'
body: <p>I am trying to build a form using Razor template engine with ASP.NET MVC 5.</p>
  
  <p>I have the following encapsulated call which I pass to the main view</p>
  
  <pre><code>public class ManagePresenter
  {
  
      public ActionFormViewModel ActionForm { get; set; }
  
      public List&lt;SelectListItem&gt; Users { get; set; }
  }
  </code></pre>
  
  <p>Then I have this view</p>
  
  <pre><code>@using(Html.BeginForm("Index", "Manage", FormMethod.Post, new { @class = "form-inline", Id = "ManageEmployeeForm" }))
  {
  
      Html.AntiForgeryToken();
      Html.HiddenFor(m =&gt; m.ActionForm.From);
      Html.HiddenFor(m =&gt; m.ActionForm.To);
  
      &lt;div class="form-group"&gt;
  
      @{
          Html.LabelFor(m =&gt; m.ActionForm.UserId, new { @class = "sr-only" });
          Html.DropDownListFor(x =&gt; x.ActionForm.UserId, Model.Users, new { @Class = "form-control" });
          Html.ValidationMessageFor(m =&gt; m.ActionForm.UserId);
      }
  
      &lt;/div&gt;
  
      &lt;div class="checkbox"&gt;
          &lt;label&gt;
              &lt;label&gt;
                  @Html.CheckBoxFor(m =&gt; m.ActionForm.ShowAlternateEntries, new { Title = "Alternate entries are entries from the telephony system that will help you compare against manual entries" })
              &lt;/label&gt;
          &lt;/label&gt;
      &lt;/div&gt;
  
      &lt;button type="submit" class="btn btn-primary" id="ManageEmployeeGetTime"&gt;View Records&lt;/button&gt;
  
  }
  </code></pre>
  
  <p>but every time I run my application I get the following error</p>
  
  <blockquote>
    <p>CS1928: 'System.Web.Mvc.HtmlHelper'
    does not contain a definition for 'DropDownListFor' and the best
    extension method overload
    'System.Web.Mvc.Html.SelectExtensions.DropDownListFor&lt;TModel,TProperty>(System.Web.Mvc.HtmlHelper&lt;TModel>,
    System.Linq.Expressions.Expression>,
    System.Collections.Generic.IEnumerable&lt;System.Web.Mvc.SelectListItem>,
    object)' has some invalid arguments</p>
  </blockquote>
  
  <p>What could be causing this error? <code>Model.Users</code> is a <code>List&lt;SelectListItem&gt;</code></p>
  
  <p>What am I missing here?</p>