Hey ho everybody,

currently I developing a press center module.

For this I made a Settings page with currently 2 Options. The problem here is that every time I submit my form I get this :

An illegal choice has been detected. Please contact the site administrator.

<?php
function presscenter_settings_form($form, &$form_state) {
 
// Define redirect path
 
$form_state['cancel_return'] = 'admin/press';
 
// Creating the Form
 
$form['press_menu'] = array(
   
'#type' => 'fieldset',
   
'#title' => t('menu settings'),
   
'#weight' => 5,
   
'#collapsible' => TRUE,
   
'#collapsed' => TRUE,
  );
 
$form['press_menu'] += presscenter_settings_menu_select();
 
$form['press_node'] = array(
   
'#type' => 'fieldset',
   
'#title' => t('node settings'),
   
'#weight' => 5,
   
'#collapsible' => TRUE,
   
'#collapsed' => TRUE,
  );
 
$form['press_node'] += presscenter_settings_node_select();
 
// Form Actions
 
$form['actions'] = array('#type' => 'actions');
 
$form['actions']['submit'] = array(
   
'#type' => 'submit',
   
'#value' => t('Save configuration'),
  );
 
$form['actions']['cancel'] = array(
   
'#type' => 'submit',
   
'#value' => t('Cancel'),
   
'#submit' => array('callback_for_cancel_button'),
   
'#limit_validation_errors' => array(),
  );
  return
$form;
}
function
presscenter_settings_form_submit($form, &$form_state){
 
dsm($form_state);
}
/**
* This function creates a select box with all menus on the current drupal
* install and returns it.
*/
function presscenter_settings_menu_select() {
 
$options = array();
 
$menus = menu_load_all();
  foreach (
$menus as $key => $menu) {
   
$options[$key] = $menu['title'];
  }
 
$form['selection'] = array(
   
'#type' => 'select',
   
'#title' => t('Press menu'),
   
'#options' => $options,
   
'#description' => t('Select a press menu witch will be displayed on the press center page.'),
  );
 
$form['enable'] = array(
   
'#type' => 'checkbox',
   
'#title' => t('Show menu on press Page.'),
   
'#default_value' => TRUE,
  );
  return
$form;
}
/**
* This function creates a select box with all contenttypes on the current drupal
* install and returns it.
*/
function presscenter_settings_node_select() {
 
$options = array();
 
$content_types = node_type_get_names();
  foreach (
$content_types as $key=>$type) {
   
$options[$key] = $type;
  }
 
$form['selection'] = array(
   
'#type' => 'select',
   
'#title' => t('Press contenttype'),
   
'#options' => $options,
   
'#description' => t('Select a press contenttype witch will be displayed on the press center page.'),
  );
 
$form['enable'] = array(
   
'#type' => 'checkbox',
   
'#title' => t('Show nodes on press Page.'),
   
'#default_value' => TRUE,
  );
  return
$form;
}
?>

It was just a name problem