diff --git a/lib/completionlib.php b/lib/completionlib.php
index a747101b6cf..c705d6194ed 100644
--- a/lib/completionlib.php
+++ b/lib/completionlib.php
@@ -592,6 +592,9 @@ class completion_info {
      * Should be called whenever a module is 'viewed' (it is up to the module how to
      * determine that). Has no effect if viewing is not set as a completion condition.
      *
+     * Note that this function must be called before you print the page header because
+     * it is possible that the navigation block may depend on it. If you call it after
+     * printing the header, it shows a developer debug warning.
      * @uses COMPLETION_VIEW_NOT_REQUIRED
      * @uses COMPLETION_VIEWED
      * @uses COMPLETION_COMPLETE
@@ -600,6 +603,11 @@ class completion_info {
      * @return void
      */
     public function set_module_viewed($cm, $userid=0) {
+        global $PAGE;
+        if ($PAGE->headerprinted) {
+            debugging('set_module_viewed must be called before header is printed',
+                    DEBUG_DEVELOPER);
+        }
         // Don't do anything if view condition is not turned on
         if ($cm->completionview == COMPLETION_VIEW_NOT_REQUIRED || !$this->is_enabled($cm)) {
             return;
@@ -932,6 +940,8 @@ class completion_info {
 
         if ($data->userid == $USER->id) {
             $SESSION->completioncache[$cm->course][$cm->id] = $data;
+            $reset = 'reset';
+            get_fast_modinfo($reset);
         }
     }
 
diff --git a/mod/chat/view.php b/mod/chat/view.php
index 1033edcf298..0475e8a2d87 100644
--- a/mod/chat/view.php
+++ b/mod/chat/view.php
@@ -79,6 +79,10 @@ $strnextsession  = get_string('nextsession', 'chat');
 
 $title = $course->shortname . ': ' . format_string($chat->name);
 
+// Mark viewed by user (if required)
+$completion = new completion_info($course);
+$completion->set_module_viewed($cm);
+
 // Initialize $PAGE
 $PAGE->set_url('/mod/chat/view.php', array('id' => $cm->id));
 $PAGE->set_title($title);
@@ -178,7 +182,4 @@ if ($chatusers = chat_get_users($chat->id, $currentgroup, $cm->groupingid)) {
     echo $OUTPUT->box_end();
 }
 
-$completion = new completion_info($course);
-$completion->set_module_viewed($cm);
-
 echo $OUTPUT->footer();
diff --git a/mod/choice/view.php b/mod/choice/view.php
index 458b53011a6..2e11c5e491e 100644
--- a/mod/choice/view.php
+++ b/mod/choice/view.php
@@ -50,6 +50,10 @@
     $PAGE->set_title(format_string($choice->name));
     $PAGE->set_heading($course->fullname);
 
+    // Mark viewed by user (if required)
+    $completion = new completion_info($course);
+    $completion->set_module_viewed($cm);
+
 /// Submit any new data if there is any
     if (data_submitted() && is_enrolled($context, NULL, 'mod/choice:choose') && confirm_sesskey()) {
         $timenow = time();
@@ -168,8 +172,3 @@
     }
 
     echo $OUTPUT->footer();
-
-/// Mark as viewed
-    $completion=new completion_info($course);
-    $completion->set_module_viewed($cm);
-
diff --git a/mod/data/view.php b/mod/data/view.php
index d94443d37b2..a8fdb05258c 100644
--- a/mod/data/view.php
+++ b/mod/data/view.php
@@ -289,6 +289,10 @@
         $PAGE->requires->js('/mod/data/js.php?d='.$data->id, true);
     }
 
+    // Mark as viewed
+    $completion = new completion_info($course);
+    $completion->set_module_viewed($cm);
+
 /// Print the page header
     // Note: MDL-19010 there will be further changes to printing header and blocks.
     // The code will be much nicer than this eventually.
@@ -730,11 +734,6 @@ if ($showactivity) {
     if (($maxcount || $mode == 'asearch') && $mode != 'single') {
         data_print_preference_form($data, $perpage, $search, $sort, $order, $search_array, $advanced, $mode);
     }
-
-/// Mark as viewed
-    $completion=new completion_info($course);
-    $completion->set_module_viewed($cm);
 }
 
 echo $OUTPUT->footer();
-
diff --git a/mod/feedback/complete.php b/mod/feedback/complete.php
index a325e9e0c6d..7f81b9b9a04 100644
--- a/mod/feedback/complete.php
+++ b/mod/feedback/complete.php
@@ -121,6 +121,10 @@
         print_error('error');
     }
 
+    // Mark activity viewed for completion-tracking
+    $completion = new completion_info($course);
+    $completion->set_module_viewed($cm);
+
     /// Print the page header
     $strfeedbacks = get_string("modulenameplural", "feedback");
     $strfeedback  = get_string("modulename", "feedback");
@@ -502,9 +506,5 @@
     ///////////////////////////////////////////////////////////////////////////
     ///////////////////////////////////////////////////////////////////////////
 
-    // Mark activity viewed for completion-tracking
-    $completion=new completion_info($course);
-    $completion->set_module_viewed($cm);
-
     echo $OUTPUT->footer();
 
diff --git a/mod/forum/view.php b/mod/forum/view.php
index 90c5d4deb84..70ac8ba23f0 100644
--- a/mod/forum/view.php
+++ b/mod/forum/view.php
@@ -97,6 +97,10 @@
         rss_add_http_header($context, 'mod_forum', $forum, $rsstitle);
     }
 
+    // Mark viewed if required
+    $completion = new completion_info($course);
+    $completion->set_module_viewed($cm);
+
 /// Print header.
     /// Add ajax-related libs for ratings if required  MDL-20119
     $PAGE->requires->yui2_lib('event');
@@ -239,8 +243,7 @@
 
             break;
     }
-    $completion=new completion_info($course);
-    $completion->set_module_viewed($cm);
+
     echo $OUTPUT->footer($course);
 
 
diff --git a/mod/glossary/view.php b/mod/glossary/view.php
index 236a52557dc..de7f2c8ca0e 100644
--- a/mod/glossary/view.php
+++ b/mod/glossary/view.php
@@ -125,6 +125,10 @@ if (!$cm->visible and !has_capability('moodle/course:viewhiddenactivities', $con
 }
 add_to_log($course->id, "glossary", "view", "view.php?id=$cm->id&tab=$tab", $glossary->id, $cm->id);
 
+// Mark as viewed
+$completion = new completion_info($course);
+$completion->set_module_viewed($cm);
+
 /// stablishing flag variables
 if ( $sortorder = strtolower($sortorder) ) {
     if ($sortorder != 'asc' and $sortorder != 'desc') {
@@ -495,8 +499,3 @@ glossary_print_tabbed_table_end();
 
 /// Finish the page
 echo $OUTPUT->footer();
-
-/// Mark as viewed
-$completion=new completion_info($course);
-$completion->set_module_viewed($cm);
-
diff --git a/mod/lesson/view.php b/mod/lesson/view.php
index b0d93c8f664..c82d5895dcd 100644
--- a/mod/lesson/view.php
+++ b/mod/lesson/view.php
@@ -45,6 +45,10 @@ if ($backtocourse) {
     redirect(new moodle_url('/course/view.php', array('id'=>$course->id)));
 }
 
+// Mark as viewed
+$completion = new completion_info($course);
+$completion->set_module_viewed($cm);
+
 $url = new moodle_url('/mod/lesson/view.php', array('id'=>$id));
 if ($pageid !== null) {
     $url->param('pageid', $pageid);
@@ -564,7 +568,3 @@ if ($pageid != LESSON_EOL) {
     echo $lessoncontent;
     echo $lessonoutput->footer();
 }
-
-/// Mark as viewed
-$completion=new completion_info($course);
-$completion->set_module_viewed($cm);
diff --git a/mod/quiz/view.php b/mod/quiz/view.php
index 7b816bc672a..ce970257688 100644
--- a/mod/quiz/view.php
+++ b/mod/quiz/view.php
@@ -55,6 +55,10 @@
 /// Log this request.
     add_to_log($course->id, "quiz", "view", "view.php?id=$cm->id", $quiz->id, $cm->id);
 
+    // Mark module as viewed
+    $completion = new completion_info($course);
+    $completion->set_module_viewed($cm);
+
 /// Initialize $PAGE, compute blocks
     $PAGE->set_url('/mod/quiz/view.php', array('id' => $cm->id));
 
@@ -382,10 +386,4 @@
     }
     echo $OUTPUT->box_end();
 
-    // Mark module as viewed (note, we do this here and not in finish_page,
-    // otherwise the 'not enrolled' error conditions would result in marking
-    // 'viewed', I think it's better if they don't.)
-    $completion=new completion_info($course);
-    $completion->set_module_viewed($cm);
-
     echo $OUTPUT->footer();
diff --git a/mod/scorm/player.php b/mod/scorm/player.php
index c45b992dcde..74d2269cd90 100644
--- a/mod/scorm/player.php
+++ b/mod/scorm/player.php
@@ -146,6 +146,10 @@
     $SESSION->scorm_mode = $mode;
     $SESSION->scorm_attempt = $attempt;
 
+    // Mark module viewed
+    $completion = new completion_info($course);
+    $completion->set_module_viewed($cm);
+
     //
     // Print the page header
     //
@@ -249,10 +253,6 @@ if (!isset($result->toctitle)) {
 
 $PAGE->requires->js_init_call('M.mod_scorm.init', array($scorm->hidenav, $scorm->hidetoc, $result->toctitle, $name, $sco->id));
 
-
-$completion=new completion_info($course);
-$completion->set_module_viewed($cm);
-
 if (!empty($forcejs)) {
     echo $OUTPUT->box(get_string("forcejavascriptmessage", "scorm"), "generalbox boxaligncenter forcejavascriptmessage");
 }
diff --git a/mod/workshop/view.php b/mod/workshop/view.php
index 2cd32a0062f..7edceb54afc 100644
--- a/mod/workshop/view.php
+++ b/mod/workshop/view.php
@@ -51,6 +51,10 @@ require_capability('mod/workshop:view', $PAGE->context);
 $workshop = new workshop($workshop, $cm, $course);
 $workshop->log('view');
 
+// Mark viewed
+$completion = new completion_info($course);
+$completion->set_module_viewed($cm);
+
 if (!is_null($editmode) && $PAGE->user_allowed_editing()) {
     $USER->editing = $editmode;
 }
@@ -538,7 +542,4 @@ case workshop::PHASE_CLOSED:
 default:
 }
 
-$completion = new completion_info($course);
-$completion->set_module_viewed($cm);
-
 echo $output->footer();