diff --git a/admin/tool/log/db/install.php b/admin/tool/log/db/install.php
index 6fccec41253..52d2d9de55d 100644
--- a/admin/tool/log/db/install.php
+++ b/admin/tool/log/db/install.php
@@ -24,14 +24,28 @@
 
 defined('MOODLE_INTERNAL') || die();
 
+/**
+ * Install the plugin.
+ */
 function xmldb_tool_log_install() {
-    global $CFG;
+    global $CFG, $DB;
 
     $enabled = array();
 
-    // For now enable only the legacy logging, this keeps 100% BC.
+    // Add data to new log only from now on.
+    if (file_exists("$CFG->dirroot/$CFG->admin/tool/log/store/standard")) {
+        $enabled[] = 'logstore_standard';
+    }
+
+    // Enable legacy log reading, but only if there are existing data.
     if (file_exists("$CFG->dirroot/$CFG->admin/tool/log/store/legacy")) {
-        $enabled[] = 'logstore_legacy';
+        unset_config('loglegacy', 'logstore_legacy');
+        // Do not enabled legacy logging if somebody installed a new
+        // site and in less than one day upgraded to 2.7.
+        $params = array('yesterday' => time() - 60*60*24);
+        if ($DB->record_exists_select('log', "time < :yesterday", $params)) {
+            $enabled[] = 'logstore_legacy';
+        }
     }
 
     set_config('enabled_stores', implode(',', $enabled), 'tool_log');
diff --git a/admin/tool/log/db/upgrade.php b/admin/tool/log/db/upgrade.php
new file mode 100644
index 00000000000..0dc059726c8
--- /dev/null
+++ b/admin/tool/log/db/upgrade.php
@@ -0,0 +1,47 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Logging support.
+ *
+ * @package    tool_log
+ * @copyright  2014 Petr Skoda {@link http://skodak.org}
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Upgrade the plugin.
+ *
+ * @param int $oldversion
+ * @return bool always true
+ */
+function xmldb_tool_log_upgrade($oldversion) {
+    global $CFG, $DB, $OUTPUT;
+
+    $dbman = $DB->get_manager();
+
+    if ($oldversion < 2014040600) {
+        // Reset logging defaults in dev branches,
+        // in production upgrade the install.php is executed instead.
+        require_once(__DIR__ . '/install.php');
+        xmldb_tool_log_install();
+        upgrade_plugin_savepoint(true, 2014040600, 'tool', 'log');
+    }
+
+    return true;
+}
diff --git a/admin/tool/log/store/legacy/settings.php b/admin/tool/log/store/legacy/settings.php
index d9ed97b5872..0a7149ecb7c 100644
--- a/admin/tool/log/store/legacy/settings.php
+++ b/admin/tool/log/store/legacy/settings.php
@@ -27,7 +27,7 @@ defined('MOODLE_INTERNAL') || die();
 if ($hassiteconfig) {
     $settings->add(new admin_setting_configcheckbox('logstore_legacy/loglegacy',
         new lang_string('loglegacy', 'logstore_legacy'),
-        new lang_string('loglegacy_help', 'logstore_legacy'), 1));
+        new lang_string('loglegacy_help', 'logstore_legacy'), 0));
 
     $settings->add(new admin_setting_configcheckbox('logguests',
         new lang_string('logguests', 'admin'),
diff --git a/admin/tool/log/version.php b/admin/tool/log/version.php
index 0838cd29665..a70afc3a21e 100644
--- a/admin/tool/log/version.php
+++ b/admin/tool/log/version.php
@@ -24,6 +24,6 @@
 
 defined('MOODLE_INTERNAL') || die();
 
-$plugin->version = 2014011300; // The current plugin version (Date: YYYYMMDDXX).
-$plugin->requires = 2014011000; // Requires this Moodle version.
+$plugin->version = 2014040600; // The current plugin version (Date: YYYYMMDDXX).
+$plugin->requires = 2014040300; // Requires this Moodle version.
 $plugin->component = 'tool_log'; // Full name of the plugin (used for diagnostics).