diff --git a/shadowsocks-csharp/Encrypt/PolarSSLEncryptor.cs b/shadowsocks-csharp/Encrypt/PolarSSLEncryptor.cs
index 1b76fe25..e14b26ab 100755
--- a/shadowsocks-csharp/Encrypt/PolarSSLEncryptor.cs
+++ b/shadowsocks-csharp/Encrypt/PolarSSLEncryptor.cs
@@ -271,7 +271,7 @@ namespace shadowsocks_csharp.Encrypt
                             PolarSSL.blowfish_free(_encryptCtx);
                             break;
                         case CIPHER_RC4:
-                            //PolarSSL.arc4_free(_encryptCtx);
+                            PolarSSL.arc4_free(_encryptCtx);
                             break;
                     }
                 }
@@ -286,7 +286,7 @@ namespace shadowsocks_csharp.Encrypt
                             PolarSSL.blowfish_free(_decryptCtx);
                             break;
                         case CIPHER_RC4:
-                            //PolarSSL.arc4_free(_decryptCtx);
+                            PolarSSL.arc4_free(_decryptCtx);
                             break;
                     }
                 }