diff --git a/lib/redmine_dmsf/webdav/custom_middleware.rb b/lib/redmine_dmsf/webdav/custom_middleware.rb
index 5f005f2f..01d4944b 100644
--- a/lib/redmine_dmsf/webdav/custom_middleware.rb
+++ b/lib/redmine_dmsf/webdav/custom_middleware.rb
@@ -20,6 +20,7 @@
 
 require "#{File.dirname(__FILE__)}/../../dav4rack"
 require "#{File.dirname(__FILE__)}/resource_proxy"
+require "#{File.dirname(__FILE__)}/dmsf_controller"
 
 module RedmineDmsf
   module Webdav
@@ -35,7 +36,7 @@ def initialize(app)
               root_uri_path: path,
               resource_class: RedmineDmsf::Webdav::ResourceProxy,
               allow_unauthenticated_options_on_root: true,
-              controller_class: DmsfController
+              controller_class: RedmineDmsf::Webdav::DmsfController
             )
           end
         end
diff --git a/lib/redmine_dmsf/webdav/dmsf_controller.rb b/lib/redmine_dmsf/webdav/dmsf_controller.rb
index 45d09bbc..a7f6cb31 100644
--- a/lib/redmine_dmsf/webdav/dmsf_controller.rb
+++ b/lib/redmine_dmsf/webdav/dmsf_controller.rb
@@ -22,7 +22,6 @@ module RedmineDmsf
   module Webdav
     # DMSF controller
     class DmsfController < Dav4rack::Controller
-      include Redmine::I18n
       include AbstractController::Callbacks
 
       around_action :switch_locale