diff --git a/apps/files_trashbin/ajax/delete.php b/apps/files_trashbin/ajax/delete.php
index 7ea0155724fa5608653f14bbdb127a07e0532ae5..7a6bd1342ea278ea53d29f66d17ef4f31cd42ecf 100644
--- a/apps/files_trashbin/ajax/delete.php
+++ b/apps/files_trashbin/ajax/delete.php
@@ -18,6 +18,7 @@ if ($path_parts['dirname'] == '.') {
 if (OCA\Files_Trashbin\Trashbin::delete($filename, $timestamp)) {
 	OCP\JSON::success(array("data" => array("filename" => $file)));
 } else {
-	OCP\JSON::error(array("data" => array("message" => "Couldn't delete ".$file. " permanently")));
+	$l = OC_L10N::get('files_trashbin');
+	OCP\JSON::error(array("data" => array("message" => $l->t("Couldn't delete %s permanently", array($file)))));
 }
 
diff --git a/apps/files_trashbin/ajax/undelete.php b/apps/files_trashbin/ajax/undelete.php
index a118d003de73b9980e1f9e922314874621152e2b..cc010979c51e28d655639c6c00f640bae69d27da 100644
--- a/apps/files_trashbin/ajax/undelete.php
+++ b/apps/files_trashbin/ajax/undelete.php
@@ -37,8 +37,10 @@ if ( $error ) {
 	foreach ( $error as $e ) {
 		$filelist .= $e.', ';
 	}
-	OCP\JSON::error(array("data" => array("message" => "Couldn't restore ".rtrim($filelist,', '), "success" => $success, "error" => $error)));
+	$l = OC_L10N::get('files_trashbin');
+	$message = $l->t("Couldn't restore %s", array(rtrim($filelist,', ')));
+	OCP\JSON::error(array("data" => array("message" => $message,
+										  "success" => $success, "error" => $error)));
 } else {
 	OCP\JSON::success(array("data" => array("success" => $success)));
 }
-
diff --git a/apps/files_versions/ajax/rollbackVersion.php b/apps/files_versions/ajax/rollbackVersion.php
index dc5a59cb4af626961652496c85f22b1bb16d6a78..2970915ac6360dddd22b47589a6d2ae8d128f73c 100644
--- a/apps/files_versions/ajax/rollbackVersion.php
+++ b/apps/files_versions/ajax/rollbackVersion.php
@@ -11,6 +11,7 @@ $revision=(int)$_GET['revision'];
 if(OCA\Files_Versions\Storage::rollback( $file, $revision )) {
 	OCP\JSON::success(array("data" => array( "revision" => $revision, "file" => $file )));
 }else{
-	OCP\JSON::error(array("data" => array( "message" => "Could not revert:" . $file )));
+	$l = OC_L10N::get('files_versions');
+	OCP\JSON::error(array("data" => array( "message" => $l->t("Could not revert: %s", array($file) ))));
 }
 
diff --git a/apps/files_versions/history.php b/apps/files_versions/history.php
index 1bd5cde44bec45d9a1616af143f9385c6a3ef737..437a3fec0652c281c9ea351e1bbab926d6550180 100644
--- a/apps/files_versions/history.php
+++ b/apps/files_versions/history.php
@@ -24,6 +24,7 @@
 OCP\User::checkLoggedIn( );
 OCP\Util::addStyle('files_versions', 'versions');
 $tmpl = new OCP\Template( 'files_versions', 'history', 'user' );
+$l = OC_L10N::get('files_versions');
 
 if ( isset( $_GET['path'] ) ) {
 
@@ -36,15 +37,21 @@ if ( isset( $_GET['path'] ) ) {
 
 		if( $versions->rollback( $path, $_GET['revert'] ) ) {
 
-			$tmpl->assign( 'outcome_stat', 'success' );
+			$tmpl->assign( 'outcome_stat', $l->t('success') );
 
-			$tmpl->assign( 'outcome_msg', "File {$_GET['path']} was reverted to version ".OCP\Util::formatDate( doubleval($_GET['revert']) ) );
+			$message = $l->t('File %s was reverted to version %s',
+				array($_GET['path'], OCP\Util::formatDate( doubleval($_GET['revert']) ) ) );
+
+			$tmpl->assign( 'outcome_msg', $message);
 
 		} else {
 
-			$tmpl->assign( 'outcome_stat', 'failure' );
+			$tmpl->assign( 'outcome_stat', $l->t('failure') );
+
+			$message = $l->t('File %s could not be reverted to version %s',
+				array($_GET['path'], OCP\Util::formatDate( doubleval($_GET['revert']) ) ) );
 
-			$tmpl->assign( 'outcome_msg', "File {$_GET['path']} could not be reverted to version ".OCP\Util::formatDate( doubleval($_GET['revert']) ) );
+			$tmpl->assign( 'outcome_msg', $message);
 
 		}
 
@@ -58,12 +65,12 @@ if ( isset( $_GET['path'] ) ) {
 
 	}else{
 
-		$tmpl->assign( 'message', 'No old versions available' );
+		$tmpl->assign( 'message', $l->t('No old versions available') );
 
 	}
 }else{
 
-	$tmpl->assign( 'message', 'No path specified' );
+	$tmpl->assign( 'message', $l->t('No path specified') );
 
 }
 
diff --git a/apps/files_versions/templates/history.php b/apps/files_versions/templates/history.php
index cc5a494f19ed0f8cad273880f91a29104fd124d4..850ece89c98fc30277d22bbc785e57e8dd61da94 100644
--- a/apps/files_versions/templates/history.php
+++ b/apps/files_versions/templates/history.php
@@ -17,7 +17,7 @@ if( isset( $_['message'] ) ) {
 	}
 
 	echo( '<strong>Versions of '.$_['path'] ).'</strong><br>';
-	echo('<p><em>Revert a file to a previous version by clicking on its revert button</em></p><br />');
+	echo('<p><em>'.$l->t('Revert a file to a previous version by clicking on its revert button').'</em></p><br />');
 
 	foreach ( $_['versions'] as $v ) {
 		echo ' ';
diff --git a/core/ajax/vcategories/add.php b/core/ajax/vcategories/add.php
index 23d00af70ab8c185ae44ab4780b9bdebf5d5dff3..16a1461be08b23c57fd00fc4ec9e15d8aa7b5acb 100644
--- a/core/ajax/vcategories/add.php
+++ b/core/ajax/vcategories/add.php
@@ -34,7 +34,7 @@ debug(print_r($category, true));
 
 $categories = new OC_VCategories($type);
 if($categories->hasCategory($category)) {
-	bailOut(OC_Contacts_App::$l10n->t('This category already exists: '.$category));
+	bailOut($l->t('This category already exists: %s', array($category)));
 } else {
 	$categories->add($category, true);
 }
diff --git a/core/ajax/vcategories/removeFromFavorites.php b/core/ajax/vcategories/removeFromFavorites.php
index ba6e95c249735d3aeed236c6a7cfb2340b5164e6..78a528caa861b1ed474c3196512778e66d9e1f07 100644
--- a/core/ajax/vcategories/removeFromFavorites.php
+++ b/core/ajax/vcategories/removeFromFavorites.php
@@ -27,12 +27,12 @@ if(is_null($type)) {
 }
 
 if(is_null($id)) {
-	bailOut($l->t('%s ID not provided.', $type));
+	bailOut($l->t('%s ID not provided.', array($type)));
 }
 
 $categories = new OC_VCategories($type);
 if(!$categories->removeFromFavorites($id, $type)) {
-	bailOut($l->t('Error removing %s from favorites.', $id));
+	bailOut($l->t('Error removing %s from favorites.', array($id)));
 }
 
 OC_JSON::success();