diff --git a/admin/module.php b/admin/module.php
index 314e57788ae..78d19e96f44 100644
--- a/admin/module.php
+++ b/admin/module.php
@@ -16,7 +16,7 @@
         }
 
         if ($module != '') {
-            require_once("$CFG->dirroot/mod/$module/lib.php");
+            include_once("$CFG->dirroot/mod/$module/lib.php");
             // if the config.html contains a hidden form field giving
             // the module name then the form does not have to prefix all
             // its variable names, we will do it here.
@@ -43,7 +43,7 @@
 
 /// Otherwise print the form.
     $module = required_param('module', PARAM_SAFEDIR);
-    require_once("$CFG->dirroot/mod/$module/lib.php");
+    include_once("$CFG->dirroot/mod/$module/lib.php");
 
     $strmodulename = get_string("modulename", $module);
 
diff --git a/admin/process_email.php b/admin/process_email.php
index 8e5091abcd0..33c8783d793 100755
--- a/admin/process_email.php
+++ b/admin/process_email.php
@@ -54,7 +54,7 @@ if ($modid == '0') { // special
 }
 else {
     $modname = get_field("modules","name","id",$modid);
-    require_once('mod/'.$modname.'/lib.php');
+    include_once('mod/'.$modname.'/lib.php');
 }
 $function = $modname.'_process_email';
 
diff --git a/course/lib.php b/course/lib.php
index 639fe77a342..7deb9719018 100644
--- a/course/lib.php
+++ b/course/lib.php
@@ -973,7 +973,7 @@ function print_overview($courses) {
     if ($modules = get_records('modules')) {
         foreach ($modules as $mod) {
             if (file_exists(dirname(dirname(__FILE__)).'/mod/'.$mod->name.'/lib.php')) {
-                require_once(dirname(dirname(__FILE__)).'/mod/'.$mod->name.'/lib.php');
+                include_once(dirname(dirname(__FILE__)).'/mod/'.$mod->name.'/lib.php');
                 $fname = $mod->name.'_print_overview';
                 if (function_exists($fname)) {
                     $fname($courses,$htmlarray);
@@ -1490,7 +1490,7 @@ function print_section_add_menus($course, $section, $modnames, $vertical=false,
                 continue;
             }
 
-            require_once("$CFG->dirroot/mod/$modname/lib.php");
+            include_once("$CFG->dirroot/mod/$modname/lib.php");
             $gettypesfunc =  $modname.'_get_types';
             if (function_exists($gettypesfunc)) {
                 $types = $gettypesfunc();
diff --git a/course/report/participation/index.php b/course/report/participation/index.php
index 9baf30c0fe9..fe9c38d9d72 100644
--- a/course/report/participation/index.php
+++ b/course/report/participation/index.php
@@ -154,7 +154,7 @@
     $module = get_record('modules','id',$moduleid);
     $modulename = get_string('modulename',$module->name);
 
-    require_once($CFG->dirroot.'/mod/'.$module->name.'/lib.php');
+    include_once($CFG->dirroot.'/mod/'.$module->name.'/lib.php');
 
     $viewfun = $module->name.'_get_view_actions';
     $postfun = $module->name.'_get_post_actions';