[Solved] Why does a schema not update if the module has been fully unistalled then reinstalled?

Here is the content of the namecards.install file, including implementation of hook_uninstall().

/**
* Implementation of hook_requirements()
*/
function namecards_requirements($phase) {
  $requirements = array();
  $t = get_t();

  // an array of the dependencies
  // where the array key is the module machine-readable name
  // and the value is the module human-readable name
  $dependencies = array(
    'content' => 'Content',
    'fieldgroup' => 'Field Group',
    'text' => 'Text',
    'nodereference' => 'Node Reference',
    'computed_field' => 'Computed Field',
    'number' => 'Number',
    'address_fld' => 'Address Field',
    'noderelationships' => 'Node Relationships',
    'noderefcreate' => 'Node Reference Create',
    'views' => 'Views',
    'jquery_ui' => 'jQuery UI',
    'date' => 'Date',
    'date_popup' => 'Date',
    'pathauto' => 'Path Auto',
  );
	
  switch ($phase) {
    case 'install':
      $error = FALSE;
      $value = '';
      foreach ($dependencies as $dependency => $module_nice_name) {
        if (!module_exists($dependency)) {
          $error = TRUE;
          $value .= $t($module_nice_name . " to be pre-installed; ");
          $severity = REQUIREMENT_ERROR;
        }
      }

      if ($error) {
        $requirements['namecards'] = array(
          'title' => $t('Namecards requires: '),
          'value' => $value . $t(' if the required modules are now installed, please enable this module again.'),
          'severity' => $severity,
        );
      }
      break;
    }

  return $requirements;
}



/**
 * Implementation of hook_install()
 */
function namecards_install() {
  if (!db_table_exists('user_namecard_settings')) {
    drupal_install_schema('user_namecard_settings');
    drupal_set_message('Table \'user_namecard_settings\' has been created');
  }
  // Create node types required by namecard module.
  _namecards_save_cck_node('position');
  _namecards_save_cck_node('department');
  _namecards_save_cck_node('event');
  _namecards_save_cck_node('organization');
  _namecards_save_cck_node('namecard');
}

/**
 * Implementation of hook_uninstall()
 */
function namecards_uninstall() {
  if (db_table_exists('user_namecard_settings')) {
    drupal_uninstall_schema('user_namecard_settings');
    drupal_set_message('Table \'user_namecard_settings\' has been deleted');
  }
  // Delete the content types used by namecards module
  node_type_delete('namecard_namecard');
  node_type_delete('namecard_event');
  node_type_delete('namecard_organization');
  node_type_delete('namecard_position');
  node_type_delete('namecard_department');
  menu_rebuild();
}

// EXAMPLE hook_update_N
// every hook_update_N will look the same
// and you will need to write a new one
// every time you update the .def.inc file

//function namecards_update_1() {
//    _namecards_save_cck_node('event');
//    return array();
//}

/**
 * Implementation of hook_schema()
 */

function namecards_schema() {
  $schema['user_namecard_settings'] = array(
    'description' => t('Stores custom UI setting information for a given user'),
    'fields' => array(
      'uid' => array(
        'type' => 'int',
        'unsigned' => TRUE,
        'not null' => TRUE,
        'default' => 0,
        'description' => t('The uid is the id of the user to which these settings belong to.'),
      ),
      'default_page' => array(
        'type' => 'int',
        'unsigned' => TRUE,
        'not null' => TRUE,
        'default' => 1, // 0 => 'browse', 1 => 'organizations', 2 => 'events'
        'description' => t('The default page shown when user logins in.'),
      ),
      'font_size' => array(
        'type' => 'int',
        'unsigned' => TRUE,
        'not null' => TRUE,
        'default' => 2, // 0 => 'Extra-small', 1 => 'Small', 2 => 'Normal', 3 => 'Large', 4 => 'Extra-large'
        'description' => t('Is the relative default font size used. total range of value is 1-5 (extra small - extra large)'),
      ),
    ),
    'primary key' => array('uid'),
  );
	
  return $schema;
}

function _namecards_save_cck_node($str) {
    module_load_include('inc', 'namecards', 'namecards.def');
    $content = _namecards_cck_export($str);

    // we do not want too many modules enabled - the content_copy and
    // alternate_content_copy modules are just needed in order to install the
    // content type, so we just require them here (require_once prevent to
    // include it more than once in case it is already enabled)
    require_once './' . drupal_get_path('module', 'content') .  '/modules/content_copy/content_copy.module';
    require_once './' . drupal_get_path('module', 'alternate_content_copy') .  '/alternate_content_copy.module';

    alternate_content_copy_import_content($content);
}