Autoalias fail with some nodes

I am experiencing this problem too. I am using [menupath-raw] for my page and panel content types. Does anyone know what is going on with this?

same problem, seems totally random.

same error for me. I really don't understand the link between all those nodes not aliased

Bumping priority down to normal unless more information can be provided on exactly how this can be reproduced.

Subscribing. The 6.x-2.x-dev release is very often updated in these days. I think, the value of the Automatic alias checkbox is lost somewhere in the space, but I do not know, which release produced this first in these days. But now, the current 6.x-2.x-dev release also producing this. Pathauto does not generate an alias in some cases. Randomly.

I wrote a possible solution: #720844: Conflict with the Pathauto module

If anybody have this problem too, than debug hook_form_alter, like this:

function pathauto_form_alter(&$form, $form_state, $form_id) {
  // Process only node forms.
  if (isset($form['type']) && isset($form['#node']) && $form['type']['#value'] .'_node_form' == $form_id) {
    $node = $form['#node'];
    $pattern = FALSE;

drupal_set_message($form['type']['#value']);
    // Find if there is an automatic alias pattern for this node type.
    if (isset($form['language'])) {
      $language = isset($form['language']['#value']) ? $form['language']['#value'] : $form['language']['#default_value'];
      $pattern = trim(variable_get('pathauto_node_'. $form['type']['#value'] .'_'. $language .'_pattern', ''));
    }
    if (!$pattern) {
      $pattern = trim(variable_get('pathauto_node_'. $form['type']['#value'] .'_pattern', ''));
      if (!$pattern) {
        $pattern = trim(variable_get('pathauto_node_pattern', ''));
      }
    }
drupal_set_message($pattern);

    // If there is a pattern, show the automatic alias checkbox.
    if ($pattern) {
      if (!isset($node->pathauto_perform_alias)) {
        if (!empty($node->nid)) {
          // If this is not a new node, compare it's current alias to the
          // alias that would be genereted by pathauto. If they are the same,
          // then keep the automatic alias enabled.
          _pathauto_include();
          $placeholders = pathauto_get_placeholders('node', $node);
          $pathauto_alias = pathauto_create_alias('node', 'return', $placeholders, "node/{$node->nid}", $node->nid, $node->type, $node->language);
drupal_set_message("{$node->path} - {$pathauto_alias} ");

The last line is the most informative. If thats are different, then pathauto will turn off the automatic alias generation.
But why different??? Which module does it? Search the REASON!

Zoltan provides good debugging info. Pathauto compares the current url alias to what would be the current generated alias. If they're different, it unchecks the checkbox.