diff --git a/conf/backend/config-autodiscover.php b/conf/backend/config-autodiscover.php
index b81a413..2c232f9 100644
--- a/conf/backend/config-autodiscover.php
+++ b/conf/backend/config-autodiscover.php
@@ -43,7 +43,7 @@
      * false - use the username only (default).
      * true - use the complete email address.
      */
-    define('USE_FULLEMAIL_FOR_LOGIN', false);
+    define('USE_FULLEMAIL_FOR_LOGIN', true);
 
     /*
      * AutoDiscover requires the username to match either the email address
diff --git a/conf/config.php b/conf/config.php
index 1c78535..b7b456d 100644
--- a/conf/config.php
+++ b/conf/config.php
@@ -54,7 +54,7 @@
      *   false - use the username only.
      *   true  - string the mobile sends as username, e.g. full email address (default).
      */
-    define('USE_FULLEMAIL_FOR_LOGIN', false);
+    define('USE_FULLEMAIL_FOR_LOGIN', true);
 
 /**********************************************************************************
  * StateMachine setting