diff --git a/Netch/Controllers/NTTController.cs b/Netch/Controllers/NTTController.cs
index 33ead8a7..889906ca 100644
--- a/Netch/Controllers/NTTController.cs
+++ b/Netch/Controllers/NTTController.cs
@@ -1,5 +1,4 @@
 using System;
-using System.Diagnostics;
 using System.IO;
 using System.Linq;
 using Netch.Utils;
diff --git a/Netch/Controllers/PrivoxyController.cs b/Netch/Controllers/PrivoxyController.cs
index d43c053b..ffe4a3d2 100644
--- a/Netch/Controllers/PrivoxyController.cs
+++ b/Netch/Controllers/PrivoxyController.cs
@@ -2,7 +2,6 @@
 using System.Text;
 using Netch.Models;
 using Netch.Servers.Socks5;
-using Netch.Utils.HttpProxyHandler;
 
 namespace Netch.Controllers
 {
diff --git a/Netch/Controllers/UpdateChecker.cs b/Netch/Controllers/UpdateChecker.cs
index 292d0f85..38eda555 100644
--- a/Netch/Controllers/UpdateChecker.cs
+++ b/Netch/Controllers/UpdateChecker.cs
@@ -1,6 +1,5 @@
 using System;
 using System.Collections.Generic;
-using System.Linq;
 using System.Net;
 using Netch.Models.GitHubRelease;
 using Netch.Utils;
diff --git a/Netch/Forms/MainForm.MenuStrip.cs b/Netch/Forms/MainForm.MenuStrip.cs
index 6e28019c..5135dfa2 100644
--- a/Netch/Forms/MainForm.MenuStrip.cs
+++ b/Netch/Forms/MainForm.MenuStrip.cs
@@ -1,18 +1,12 @@
 using System;
-using System.Collections.Generic;
 using System.IO;
-using System.Linq;
 using System.Net;
-using System.Text;
 using System.Threading.Tasks;
 using System.Windows.Forms;
 using Netch.Controllers;
 using Netch.Forms.Mode;
 using Netch.Models;
-using Netch.Properties;
 using Netch.Utils;
-using Netch.Utils.HttpProxyHandler;
-using Newtonsoft.Json;
 
 namespace Netch.Forms
 {
diff --git a/Netch/Forms/MainForm.Status.cs b/Netch/Forms/MainForm.Status.cs
index 89bd6d42..aadb2474 100644
--- a/Netch/Forms/MainForm.Status.cs
+++ b/Netch/Forms/MainForm.Status.cs
@@ -2,9 +2,7 @@
 using System.Collections.Generic;
 using System.Drawing;
 using System.Linq;
-using Netch.Controllers;
 using Netch.Models;
-using Netch.Servers.Socks5;
 using Netch.Utils;
 
 namespace Netch.Forms
diff --git a/Netch/Forms/SettingForm.cs b/Netch/Forms/SettingForm.cs
index 12e7c430..28c6e9e3 100644
--- a/Netch/Forms/SettingForm.cs
+++ b/Netch/Forms/SettingForm.cs
@@ -1,7 +1,6 @@
 using Netch.Utils;
 using System;
 using System.Collections.Generic;
-using System.ComponentModel;
 using System.Drawing;
 using System.IO;
 using System.Linq;
diff --git a/Netch/Forms/SubscribeForm.cs b/Netch/Forms/SubscribeForm.cs
index e9fef796..a4c3558f 100644
--- a/Netch/Forms/SubscribeForm.cs
+++ b/Netch/Forms/SubscribeForm.cs
@@ -1,5 +1,4 @@
 using System;
-using System.ComponentModel;
 using System.Linq;
 using System.Windows.Forms;
 using Netch.Models;
diff --git a/Netch/Models/Setting.cs b/Netch/Models/Setting.cs
index b87f508a..f2578317 100644
--- a/Netch/Models/Setting.cs
+++ b/Netch/Models/Setting.cs
@@ -1,6 +1,4 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
+using System.Collections.Generic;
 
 namespace Netch.Models
 {
diff --git a/Netch/Servers/ShadowsocksR/SSRController.cs b/Netch/Servers/ShadowsocksR/SSRController.cs
index f62eec3c..43efed4c 100644
--- a/Netch/Servers/ShadowsocksR/SSRController.cs
+++ b/Netch/Servers/ShadowsocksR/SSRController.cs
@@ -1,7 +1,6 @@
 using System.Text;
 using Netch.Controllers;
 using Netch.Models;
-using Netch.Utils;
 
 namespace Netch.Servers.ShadowsocksR
 {
diff --git a/Netch/Servers/Trojan/TrojanController.cs b/Netch/Servers/Trojan/TrojanController.cs
index fe2490bf..2b2aaeb9 100644
--- a/Netch/Servers/Trojan/TrojanController.cs
+++ b/Netch/Servers/Trojan/TrojanController.cs
@@ -3,7 +3,6 @@ using System.IO;
 using Netch.Controllers;
 using Netch.Models;
 using Netch.Servers.Trojan.Models;
-using Netch.Utils;
 using Newtonsoft.Json;
 
 namespace Netch.Servers.Trojan
diff --git a/Netch/Servers/VLESS/VLESS.cs b/Netch/Servers/VLESS/VLESS.cs
index fead2159..c8cfaeb4 100644
--- a/Netch/Servers/VLESS/VLESS.cs
+++ b/Netch/Servers/VLESS/VLESS.cs
@@ -1,5 +1,4 @@
 using System.Collections.Generic;
-using Netch.Models;
 using Netch.Servers.VMess;
 
 namespace Netch.Servers.VLESS
diff --git a/Netch/Servers/VMess/VMess.cs b/Netch/Servers/VMess/VMess.cs
index c826001f..a0b0b065 100644
--- a/Netch/Servers/VMess/VMess.cs
+++ b/Netch/Servers/VMess/VMess.cs
@@ -1,4 +1,3 @@
-using System;
 using System.Collections.Generic;
 using Netch.Models;
 
diff --git a/Netch/Utils/Bandwidth.cs b/Netch/Utils/Bandwidth.cs
index 852f4032..43194b78 100644
--- a/Netch/Utils/Bandwidth.cs
+++ b/Netch/Utils/Bandwidth.cs
@@ -1,15 +1,12 @@
-using System;
-using System.Collections.Generic;
+using System.Collections.Generic;
 using System.Diagnostics;
 using System.Linq;
 using System.Threading.Tasks;
 using Microsoft.Diagnostics.Tracing.Parsers;
 using Microsoft.Diagnostics.Tracing.Session;
 using Netch.Controllers;
-using Netch.Forms;
 using Netch.Models;
 using Netch.Servers.Shadowsocks;
-using Netch.Servers.Socks5;
 
 namespace Netch.Utils
 {
diff --git a/Netch/Utils/HttpProxyHandler/PACServerHandle.cs b/Netch/Utils/HttpProxyHandler/PACServerHandle.cs
index 84aefa7a..fcad45a0 100644
--- a/Netch/Utils/HttpProxyHandler/PACServerHandle.cs
+++ b/Netch/Utils/HttpProxyHandler/PACServerHandle.cs
@@ -1,7 +1,6 @@
 using System;
 using System.Collections;
 using System.Collections.Generic;
-using System.Globalization;
 using System.IO;
 using System.Net;
 using System.Text;
diff --git a/Netch/Utils/ICSHelper.cs b/Netch/Utils/ICSHelper.cs
index bbb7662f..d0dea2d6 100644
--- a/Netch/Utils/ICSHelper.cs
+++ b/Netch/Utils/ICSHelper.cs
@@ -1,5 +1,4 @@
 using System;
-using System.Linq;
 using System.Management;
 using Netch.Controllers;
 using Netch.Models.WinFW;
diff --git a/Netch/Utils/ServerHelper.cs b/Netch/Utils/ServerHelper.cs
index c6da5154..1c45afb3 100644
--- a/Netch/Utils/ServerHelper.cs
+++ b/Netch/Utils/ServerHelper.cs
@@ -13,7 +13,7 @@ namespace Netch.Utils
 
         static ServerHelper()
         {
-            var serversUtilsTypes = Assembly.GetExecutingAssembly().GetExportedTypes().Where(type => type.GetInterfaces().Any(t => t == typeof(IServerUtil)));
+            var serversUtilsTypes = Assembly.GetExecutingAssembly().GetExportedTypes().Where(type => type.GetInterfaces().Contains(typeof(IServerUtil)));
             ServerUtils = serversUtilsTypes.Select(t => (IServerUtil) Activator.CreateInstance(t)).OrderBy(util => util.Priority);
         }
 
diff --git a/Netch/Utils/ShareLink.cs b/Netch/Utils/ShareLink.cs
index b40eb1d1..829a565b 100644
--- a/Netch/Utils/ShareLink.cs
+++ b/Netch/Utils/ShareLink.cs
@@ -5,7 +5,6 @@ using System.Linq;
 using System.Text;
 using Netch.Servers.Shadowsocks;
 using Netch.Servers.Shadowsocks.Models;
-using Netch.Servers.VMess;
 using Newtonsoft.Json;
 using Newtonsoft.Json.Linq;
 using Server = Netch.Models.Server;