CheckSum Profile Update
I'm not sure which CMS you are using but, per the civicrm wiki page, the URL Checksum for standard Profiles (edit mode) is as below:

To send people to a profile use this path where N is the ID of the Profile you want to send them to:

Drupal: http://www.myorganization.org/civicrm/profile/edit?reset=1&amp;gid=N&amp;{contact.checksum}&amp;id={contact.contact_id}
Joomla!: http://www.myorganization.org/index.php?option=com_civicrm&amp;task=civicrm/profile/edit&amp;reset=1&amp;gid=N&amp;{contact.checksum}&amp;id={contact.contact_id}
WordPress: http://www.myorganization.org/?page=CiviCRM&amp;q=civicrm/profile/edit&amp;reset=1&amp;gid=N&amp;{contact.checksum}&amp;id={contact.contact_id}


Hope this helps and solves your problem.