title: How do I solve an <authentication mode="Forms"> Server Error?
body: <p>I've made an ASP.NETapplication in Visual Studio. When it was ready I did &quot;Publish Website&quot;. I placed the created folder on my website.</p>
  <p>When I go to the application on my site, I get the following error:</p>
  <blockquote>
  <h3>Server Error in '/' Application.</h3>
  <h4><strong>Configuration Error</strong></h4>
  <p><strong>Description</strong>: An error occurred during the processing of a configuration file required to service this request. Please review the specific error details below and modify your configuration file appropriately.</p>
  <p><strong>Parser Error Message</strong>: It is an error to use a section registered as  <code>allowDefinition='MachineToApplication'</code> beyond application level. This error  can be caused by a virtual directory not being configured as an application  in IIS.</p>
  <p><strong>Source Error:</strong></p>
  <pre><code>Line 47:      ASP.NET to identify an incoming user. 
  Line 48:      --&gt;
  Line 49:      &lt;authentication mode=&quot;Forms&quot; /&gt;
  Line 50:      
  Line 51:      &lt;customErrors mode=&quot;Off&quot;&gt;
  </code></pre>
  <p><strong>Source File:</strong>
  \CLST_SMB1IIS\WebfarmData$\WebData\winckelmans.net\wwwroot\bookstore\web.config
  <strong>Line:</strong> 49</p>
  </blockquote>
  <p>How do I solve this?</p>