diff --git a/ChangeLog b/ChangeLog
index bc236ed96..ee50b5b33 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -19,6 +19,7 @@ $HeadURL$
 - bug #1664212 querywindow loses url encoded characters
 - bug #1682044 Export file even if file not selected
 - bug #1672789 Undefined offset: 4 in sqlparser.lib.php #1674
+- bug #1662976 Authentication fails when controluser/pass is set
 - [gui] avoid displaying a wide selector in server selection
 + [core] added PMA_fatalError() and made use of it
 . [i18n] use generic $strOptions
diff --git a/libraries/common.lib.php b/libraries/common.lib.php
index 94b73300e..45bb6300e 100644
--- a/libraries/common.lib.php
+++ b/libraries/common.lib.php
@@ -3378,10 +3378,12 @@ if (! defined('PMA_MINIMUM_COMMON')) {
         // get the privileges list for the current user but the true user link
         // must be open after this one so it would be default one for all the
         // scripts)
+        $controllink = false;
         if ($cfg['Server']['controluser'] != '') {
             $controllink = PMA_DBI_connect($cfg['Server']['controluser'],
                 $cfg['Server']['controlpass'], true);
-        } else {
+        }
+        if (! $controllink) {
             $controllink = PMA_DBI_connect($cfg['Server']['user'],
                 $cfg['Server']['password'], true);
         } // end if ... else
diff --git a/libraries/dbi/mysql.dbi.lib.php b/libraries/dbi/mysql.dbi.lib.php
index 489e2b782..187410faf 100644
--- a/libraries/dbi/mysql.dbi.lib.php
+++ b/libraries/dbi/mysql.dbi.lib.php
@@ -78,7 +78,13 @@ function PMA_DBI_connect($user, $password, $is_controluser = FALSE) {
         $link = PMA_DBI_real_connect($cfg['Server']['host'] . $server_port . $server_socket, $user, '', empty($client_flags) ? NULL : $client_flags);
     }
 
-    if (empty($link)) {
+        debug_print_backtrace();
+        die;
+    if (empty($link) && ! $is_controluser) {
+        if ($is_controluser) {
+            define('PMA_DBI_CONNECT_FAILED_CONTROLUSER', true);
+            return false;
+        }
         PMA_auth_fails();
     } // end if
 
diff --git a/libraries/dbi/mysqli.dbi.lib.php b/libraries/dbi/mysqli.dbi.lib.php
index d8149f4b0..3e4e896ac 100644
--- a/libraries/dbi/mysqli.dbi.lib.php
+++ b/libraries/dbi/mysqli.dbi.lib.php
@@ -107,6 +107,10 @@ function PMA_DBI_connect($user, $password, $is_controluser = false)
     }
 
     if ($return_value == false) {
+        if ($is_controluser) {
+            define('PMA_DBI_CONNECT_FAILED_CONTROLUSER', true);
+            return false;
+        }
         PMA_auth_fails();
     } // end if
 
diff --git a/main.php b/main.php
index 3b95649b2..6b5611322 100644
--- a/main.php
+++ b/main.php
@@ -345,8 +345,8 @@ if (! empty($GLOBALS['PMA_errors']) && is_array($GLOBALS['PMA_errors'])) {
  * modified: 2004-05-05 mkkeck
  */
 if ($server != 0
-    && $cfg['Server']['user'] == 'root'
-    && $cfg['Server']['password'] == '') {
+ && $cfg['Server']['user'] == 'root'
+ && $cfg['Server']['password'] == '') {
     echo '<div class="warning">' . $strInsecureMySQL . '</div>' . "\n";
 }
 
@@ -391,6 +391,9 @@ if (defined('PMA_MYSQL_INT_VERSION') && PMA_MYSQL_INT_VERSION < 32332) {
     echo '<div class="warning">' . sprintf($strUpgrade, 'MySQL', '3.23.32') . '</div>' . "\n";
 }
 
+/**
+ * Warning about different MySQL library and server version
+ */
 if ($server > 0 && PMA_MYSQL_CLIENT_API !== PMA_MYSQL_INT_VERSION) {
     echo '<div class="warning">'
      . PMA_sanitize(sprintf($strMysqlLibDiffersServerVersion,
@@ -399,6 +402,14 @@ if ($server > 0 && PMA_MYSQL_CLIENT_API !== PMA_MYSQL_INT_VERSION) {
      . '</div>' . "\n";
 }
 
+/**
+ * Warning about wrong controluser settings
+ */
+$strControluserFailed = 'Connection for controluser as defined in your config.inc.php failed.';
+if (defined('PMA_DBI_CONNECT_FAILED_CONTROLUSER')) {
+    echo '<div class="warning">' . $strControluserFailed . '</div>' . "\n";
+}
+
 if (defined('PMA_WARN_FOR_MCRYPT')) {
     echo '<div class="warning">' . PMA_sanitize(sprintf($strCantLoad, 'mcrypt')) . '</div>' . "\n";
 }