diff --git a/changelog.txt b/changelog.txt
index f6ba31f49..31b9e75f3 100644
--- a/changelog.txt
+++ b/changelog.txt
@@ -1,5 +1,6 @@
 2.1.27
 34/
+ #2549 Missing library
  #2534 Syntax error in share permissions
 
 33/
diff --git a/sources/main.functions.php b/sources/main.functions.php
index 105aac611..e35406e73 100644
--- a/sources/main.functions.php
+++ b/sources/main.functions.php
@@ -2573,6 +2573,9 @@ function ldapPosixAndWindows($username, $password, $SETTINGS)
         $ldap_suffix = "@".substr(html_entity_decode($username), 0, strpos(html_entity_decode($username), '\\'));
         $username = substr(html_entity_decode($username), strpos(html_entity_decode($username), '\\') + 1);
     }
+
+    //load ClassLoader
+    include_once $SETTINGS['cpassman_dir'].'/sources/SplClassLoader.php';
     
     $adldap = new SplClassLoader('adLDAP', '../includes/libraries/LDAP');
     $adldap->register();