diff --git a/CHANGES b/CHANGES
index 1bc2a74e..cc7d705e 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,11 @@
+3.4.2.1 2016-12-30
+- Refine Traditional Chinese translation by LNDDYL
+- sysproxy: reduce false positives on virus detection
+- sysproxy: set LAN proxy settings even if RAS query fails
+- privoxy: drop obsolete tray area refreshing code
+- Fix auto startup
+- Bug fixes and improvements
+
 3.4.2 2016-12-16
 - Fix null ref in TCPRelay. (#940)
 - Bring Privoxy back. (#948)
diff --git a/shadowsocks-csharp/Controller/Service/UpdateChecker.cs b/shadowsocks-csharp/Controller/Service/UpdateChecker.cs
index 6f121fba..1f0ed0c4 100644
--- a/shadowsocks-csharp/Controller/Service/UpdateChecker.cs
+++ b/shadowsocks-csharp/Controller/Service/UpdateChecker.cs
@@ -24,7 +24,7 @@ namespace Shadowsocks.Controller
         public string LatestVersionLocalName;
         public event EventHandler CheckUpdateCompleted;
 
-        public const string Version = "3.4.2";
+        public const string Version = "3.4.2.1";
 
         private class CheckUpdateTimer : System.Timers.Timer
         {