diff --git a/lang/en/repository.php b/lang/en/repository.php
index babe63652e0..49050f045da 100644
--- a/lang/en/repository.php
+++ b/lang/en/repository.php
@@ -88,6 +88,7 @@ $string['entername'] = 'Please enter folder name';
 $string['enternewname'] = 'Please enter the new file name';
 $string['error'] = 'An unknown error occurred!';
 $string['errornotyourfile'] = 'You cannot pick file which is not added by your';
+$string['erroruniquename'] = 'Repository instance name should be unique';
 $string['existingrepository'] = 'This repository already exists';
 $string['federatedsearch'] = 'Federated search';
 $string['filename'] = 'Filename';
diff --git a/repository/filesystem/lib.php b/repository/filesystem/lib.php
index 12ab6699803..da3e6ef5c5c 100644
--- a/repository/filesystem/lib.php
+++ b/repository/filesystem/lib.php
@@ -163,7 +163,7 @@ class repository_filesystem extends repository {
                 }
                 if (empty($choices)) {
                     $mform->addElement('static', '', '', get_string('nosubdir', 'repository_filesystem', $path));
-                    $mform->addElement('hidden', 'fs_path', $fieldname, '');
+                    $mform->addElement('hidden', 'fs_path', '');
                 } else {
                     $mform->addElement('select', 'fs_path', $fieldname, $choices);
                     $mform->addElement('static', null, '',  get_string('information','repository_filesystem', $path));
@@ -189,4 +189,10 @@ class repository_filesystem extends repository {
             return false;
         }
     }
+    public static function instance_form_validation($mform, $data, $errors) {
+        if (empty($data['fs_path'])) {
+            $errors['fs_path'] = get_string('invalidadminsettingname', 'error', 'fs_path');
+        }
+        return $errors;
+    }
 }
diff --git a/repository/lib.php b/repository/lib.php
index 453e0679c44..eb2109653f7 100644
--- a/repository/lib.php
+++ b/repository/lib.php
@@ -1533,6 +1533,10 @@ abstract class repository {
         return array();
     }
 
+    public static function instance_form_validation($mform, $data, $errors) {
+        return $errors;
+    }
+
     public function get_short_filename($str, $maxlength) {
         if (strlen($str) >= $maxlength) {
             return trim(substr($str, 0, $maxlength)).'...';
@@ -1633,13 +1637,22 @@ final class repository_instance_form extends moodleform {
 
     public function validation($data) {
         global $DB;
-
         $errors = array();
+        $plugin = $this->_customdata['plugin'];
+        $instance = (isset($this->_customdata['instance'])
+                && is_subclass_of($this->_customdata['instance'], 'repository'))
+            ? $this->_customdata['instance'] : null;
+        if (!$instance) {
+            $errors = repository::static_function($plugin, 'instance_form_validation', $this, $data, $errors);
+        } else {
+            $errors = $instance->instance_form_validation($this, $data, $errors);
+        }
+
         $sql = "SELECT count('x')
                   FROM {repository_instances} i, {repository} r
                  WHERE r.type=:plugin AND r.id=i.typeid AND i.name=:name";
         if ($DB->count_records_sql($sql, array('name' => $data['name'], 'plugin' => $data['plugin'])) > 1) {
-            $errors = array('name' => get_string('err_uniquename', 'repository'));
+            $errors['name'] = get_string('erroruniquename', 'repository');
         }
 
         return $errors;