diff --git a/wp-admin/admin-functions.php b/wp-admin/admin-functions.php
index e6f549ff15..2f0d81e5f7 100644
--- a/wp-admin/admin-functions.php
+++ b/wp-admin/admin-functions.php
@@ -41,7 +41,7 @@ function get_nested_categories($default = 0) {
    $array_category = get_object_vars($category);
    $me = 0 + $category->cat_ID;
    $parent = 0 + $category->category_parent;
-   $array_category['children'] = $result[$me];
+	if (isset($result[$me]))   $array_category['children'] = $result[$me];
    $array_category['checked'] = in_array($category->cat_ID, $checked_categories);
    $array_category['cat_name'] = stripslashes($category->cat_name);
    $result[$parent][] = $array_category;
@@ -58,7 +58,7 @@ function write_nested_categories($categories) {
 
    if(isset($category['children'])) {
      echo "\n<span class='cat-nest'>\n";
-     write_nested_categories($category['children'], $count);
+     write_nested_categories($category['children']);
      echo "</span>\n";
    }
  }
diff --git a/wp-admin/admin-header.php b/wp-admin/admin-header.php
index 4ae400145a..248d74bcc4 100644
--- a/wp-admin/admin-header.php
+++ b/wp-admin/admin-header.php
@@ -71,7 +71,7 @@ setTimeout("redirect();", 600);
 } // redirect
 ?>
 
-<?php if ($xfn) : ?>
+<?php if (isset($xfn)) : ?>
 <script language="javascript" type="text/javascript">
 //<![CDATA[
 
diff --git a/wp-admin/edit-form-advanced.php b/wp-admin/edit-form-advanced.php
index 891ff6bf0e..fd503996af 100644
--- a/wp-admin/edit-form-advanced.php
+++ b/wp-admin/edit-form-advanced.php
@@ -3,7 +3,7 @@ $messages[1] = __('Post updated');
 $messages[2] = __('Custom field updated');
 $messages[3] = __('Custom field deleted.');
 ?>
-<?php if ($_GET['message']) : ?>
+<?php if (isset($_GET['message'])) : ?>
 <div class="updated"><p><?php echo $messages[$_GET['message']]; ?></p></div>
 <?php endif; ?>
 <div class="wrap">
@@ -52,7 +52,7 @@ $saveasdraft = '<input name="save" type="submit" id="save" tabindex="6" value="'
 <input type="hidden" name="user_ID" value="<?php echo $user_ID ?>" />
 <input type="hidden" name="action" value='<?php echo $form_action ?>' />
 <?php echo $form_extra ?>
-<?php if (2 > $_GET['message']) : ?>
+<?php if (isset($_GET['message']) && 2 > $_GET['message']) : ?>
 <script type="text/javascript">
 <!--
 function focusit() {
diff --git a/wp-admin/menu.php b/wp-admin/menu.php
index c77e0c2ce2..5beb3d71e2 100644
--- a/wp-admin/menu.php
+++ b/wp-admin/menu.php
@@ -20,6 +20,7 @@ $menu = array(
 );
 
 $self = preg_replace('|.*/wp-admin/|i', '', $_SERVER['PHP_SELF']);
+if (!isset($parent_file)) $parent_file = '';
 foreach ($menu as $item) {
 	$class = '';
 
diff --git a/wp-admin/post.php b/wp-admin/post.php
index f409fef31f..13f0b21e4d 100644
--- a/wp-admin/post.php
+++ b/wp-admin/post.php
@@ -230,7 +230,6 @@ case 'edit':
 
 		include('edit-form-advanced.php');
 
-		include(ABSPATH.'wp-blog-header.php');
 		$post = $wpdb->get_row("SELECT * FROM $tableposts WHERE ID = '$post_ID'");
 		?>
 <div id='preview' class='wrap'>
diff --git a/wp-blog-header.php b/wp-blog-header.php
index 0c884920c8..67cfbc9268 100644
--- a/wp-blog-header.php
+++ b/wp-blog-header.php
@@ -6,7 +6,7 @@ $curpath = dirname(__FILE__).'/';
 if (!file_exists($curpath . '/wp-config.php'))
     die("There doesn't seem to be a <code>wp-config.php</code> file. I need this before we can get started. Need more help? <a href='http://wordpress.org/docs/faq/#wp-config'>We got it</a>. You can <a href='wp-admin/install-config.php'>create a <code>wp-config.php</code> file through a web interface</a>, but this doesn't work for all server setups. The safest way is to manually create the file.");
 
-require($curpath.'/wp-config.php');
+require_once($curpath . '/wp-config.php');
 
 /* Process PATH_INFO, if set. */
 $path_info = array();