renewed certificate and app provisioning profile, but it still said provisioning profile expired
<p>My certificate had expired, so I renewed the certificate and created the new provisioning profile with same app bundle id(app identifier).</p>

<p>I added the certificate file to 'keychain access' and added the provisioning profile to 'xcode'.</p>

<p>I could see the new provisioning profile in Organizer</p>

<p><img src="http://i.stack.imgur.com/guhBh.png" alt="enter image description here"></p>

<p>but when I installed the ad hoc version to my ipod, it still reported provisioning profile expired
  :-(</p>

<p><img src="http://i.stack.imgur.com/WjprR.png" alt="enter image description here"></p>

<p>Welcome any comment</p>

<p>Thanks</p>
