diff --git a/Server/Core/Helper/UPnP.cs b/Server/Core/Helper/UPnP.cs
index 42358abb..b91c4b92 100644
--- a/Server/Core/Helper/UPnP.cs
+++ b/Server/Core/Helper/UPnP.cs
@@ -1,8 +1,6 @@
-using System;
-using System.Net;
-using System.Net.Sockets;
+using System.Collections.Generic;
 using System.Threading;
-using NATUPNPLib;
+using Mono.Nat;
 
 namespace xServer.Core.Helper
 {
@@ -10,85 +8,58 @@ internal static class UPnP
     {
         public static bool IsPortForwarded { get; private set; }
         public static ushort Port { get; private set; }
+        private static readonly HashSet<INatDevice> Devices = new HashSet<INatDevice>();
 
         public static void ForwardPort(ushort port)
         {
             Port = port;
+            NatUtility.DeviceFound += DeviceFound;
+            NatUtility.DeviceLost += DeviceLost;
+            NatUtility.StartDiscovery();
 
             new Thread(() =>
             {
-                string ipAddr = string.Empty;
-                int retry = 0;
-
-                do
+                while (Devices.Count == 0) // wait until first device found
                 {
-                    try
-                    {
-                        TcpClient c = null;
-                        EndPoint endPoint;
-                        try
-                        {
-                            c = new TcpClient();
-                            c.Connect("www.google.com", 80);
-                            endPoint = c.Client.LocalEndPoint;
-                        }
-                        finally
-                        {
-                            // Placed in here to make sure that a failed TcpClient will never linger!
-                            if (c != null)
-                            {
-                                c.Close();
-                            }
-                        }
-
-                        if (endPoint != null)
-                        {
-                            ipAddr = endPoint.ToString();
-                            int index = ipAddr.IndexOf(":", StringComparison.Ordinal);
-                            ipAddr = ipAddr.Remove(index);
-
-                            // We got through successfully and with an endpoint and a parsed IP address. We may exit the loop.
-                            break;
-                        }
-                        else
-                        {
-                            retry++;
-                        }
-                    }
-                    catch
-                    {
-                        retry++;
-                    }
-                } while (retry < 5);
-
-                if (string.IsNullOrEmpty(ipAddr)) // If we can't successfully connect
-                    return;
+                    Thread.Sleep(1000);
+                }
 
                 try
                 {
-                    IStaticPortMappingCollection portMap = new UPnPNAT().StaticPortMappingCollection;
-                    if (portMap != null)
-                        portMap.Add(port, "TCP", port, ipAddr, true, "xRAT 2.0 UPnP");
+                    foreach (var device in Devices)
+                    {
+                        device.CreatePortMap(new Mapping(Protocol.Tcp, Port, Port));
+                    }
                     IsPortForwarded = true;
                 }
-                catch
+                catch (MappingException)
                 {
+                    IsPortForwarded = false;
                 }
             }).Start();
         }
 
+        private static void DeviceFound(object sender, DeviceEventArgs args)
+        {
+            Devices.Add(args.Device);
+        }
+
+        private static void DeviceLost(object sender, DeviceEventArgs args)
+        {
+            Devices.Remove(args.Device);
+        }
+
         public static void RemovePort()
         {
-            try
-            {
-                IStaticPortMappingCollection portMap = new UPnPNAT().StaticPortMappingCollection;
-                if (portMap != null)
-                    portMap.Remove(Port, "TCP");
-                IsPortForwarded = false;
-            }
-            catch
+            foreach (var device in Devices)
             {
+                if (device.GetSpecificMapping(Protocol.Tcp, Port).PublicPort > 0) // if port map exists
+                {
+                    device.DeletePortMap(new Mapping(Protocol.Tcp, Port, Port));
+                }
             }
+            IsPortForwarded = false;
+            NatUtility.StopDiscovery();
         }
     }
 }
\ No newline at end of file
diff --git a/Server/Forms/FrmSettings.cs b/Server/Forms/FrmSettings.cs
index 272271b1..c1878c2f 100644
--- a/Server/Forms/FrmSettings.cs
+++ b/Server/Forms/FrmSettings.cs
@@ -1,6 +1,7 @@
 using System;
 using System.Globalization;
 using System.Windows.Forms;
+using xServer.Core.Helper;
 using xServer.Core.Misc;
 using xServer.Core.Networking;
 using xServer.Settings;
@@ -47,8 +48,8 @@ private void btnListen_Click(object sender, EventArgs e)
             {
                 try
                 {
-                    if (chkUseUpnp.Checked && !Core.Helper.UPnP.IsPortForwarded)
-                        Core.Helper.UPnP.ForwardPort(ushort.Parse(ncPort.Value.ToString(CultureInfo.InvariantCulture)));
+                    if (chkUseUpnp.Checked && !UPnP.IsPortForwarded)
+                        UPnP.ForwardPort(ushort.Parse(ncPort.Value.ToString(CultureInfo.InvariantCulture)));
                     if(chkNoIPIntegration.Checked)
                         NoIpUpdater.Start();
                     _listenServer.Listen(ushort.Parse(ncPort.Value.ToString(CultureInfo.InvariantCulture)));
@@ -65,8 +66,8 @@ private void btnListen_Click(object sender, EventArgs e)
                 try
                 {
                     _listenServer.Disconnect();
-                    if (Core.Helper.UPnP.IsPortForwarded)
-                        Core.Helper.UPnP.RemovePort();
+                    if (UPnP.IsPortForwarded)
+                        UPnP.RemovePort();
                 }
                 finally
                 {
diff --git a/Server/Server.csproj b/Server/Server.csproj
index 04dd5a4e..958e2518 100644
--- a/Server/Server.csproj
+++ b/Server/Server.csproj
@@ -51,6 +51,9 @@
       <SpecificVersion>False</SpecificVersion>
       <HintPath>lib\Mono.Cecil.dll</HintPath>
     </Reference>
+    <Reference Include="Mono.Nat">
+      <HintPath>lib\Mono.Nat.dll</HintPath>
+    </Reference>
     <Reference Include="System" />
     <Reference Include="System.Data" />
     <Reference Include="System.Drawing" />
@@ -436,17 +439,6 @@
   <ItemGroup>
     <Content Include="xRAT-64x64.ico" />
   </ItemGroup>
-  <ItemGroup>
-    <COMReference Include="NATUPNPLib">
-      <Guid>{1C565858-F302-471E-B409-F180AA4ABEC6}</Guid>
-      <VersionMajor>1</VersionMajor>
-      <VersionMinor>0</VersionMinor>
-      <Lcid>0</Lcid>
-      <WrapperTool>tlbimp</WrapperTool>
-      <Isolated>False</Isolated>
-      <EmbedInteropTypes>True</EmbedInteropTypes>
-    </COMReference>
-  </ItemGroup>
   <ItemGroup />
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
diff --git a/Server/lib/Interop.NATUPNPLib.dll b/Server/lib/Interop.NATUPNPLib.dll
deleted file mode 100644
index 3a0309ed..00000000
Binary files a/Server/lib/Interop.NATUPNPLib.dll and /dev/null differ