第一次加载xhtml时出错？

Question

它有时只会在我第一次加载应用时发生。

This XML file does not appear to have any style information associated with it. The document tree is shown below.
<partial-response id="j_id1">
  <error>
  <error-name>class javax.faces.application.ViewExpiredException</error-name>
  <error-message>
    <![CDATA[ See your server log for more information ]]>
  </error-message>
  </error>
</partial-response>

知道它可能是什么。