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Tcp Server Only Allowing 1 Client

Server.cs - https://hastebin.com/enajinewij.cs
Client.cs - https://hastebin.com/iriperubur.cs
I have tried both running the Client on another PC and running it on one PC, but both result in the Client not being able to receive or send any messages.
I CANT portforward. I am using Hamachi for the IP Address. Both client and server are connected to my Network and are using the Hamachi IP Address. I am using PDA Net to connect to the internet from my PC.
The Server does not see them connect at all. Nor does the Server get any messages from them. Currently only the Server can send messages, and only it can get them.
I am not getting ANY errors at all, so I am not sure how I should handle solving this issue as it's my first time working with networking.

At first you create a TcpListener and you call StartLis() that does BeginAcceptTcpClient. However in AcceptTCPClient you create a new TcpListener and BeginAcceptTcpClient is not called.
You don't have to create a new listener for each connection, but you do have to call BeginAcceptTcpclient again:
private void AcceptTCPClient(IAsyncResult ar)
{
TcpListener Lis = (TcpListener)ar.AsyncState;
Clients.Add(new ServerClient(Lis.EndAcceptTcpClient(ar)));
StartLis(); // this will call BeginAcceptTcpClient again
}

How to access remote object from other computer in remoting

I have a server object as
TcpChannel tcp = new TcpChannel(1234);
ChannelServices.RegisterChannel(tcp, false);
string s = ConfigurationManager.AppSettings["remote"];
RemotingConfiguration.RegisterWellKnownServiceType(typeof(TestRemoting.InitialClass1), "TestRemoting", WellKnownObjectMode.Singleton);
Console.WriteLine("Server is running on 1234 channel...");
Console.WriteLine("Press Enter to Stop");
Console.ReadLine();
and I am accessing that object in mu client form like
InitialClass1 Icls = (InitialClass1)Activator.GetObject(typeof(InitialClass1), "tcp://localhost:1234//TestRemoting");
Now I am keeping my remote object in another computer. How can I access my server object from that computer. If I access the server object from my (local) computer, I will use
"tcp://localhost:1234//TestRemoting"
I am using localhost here, because my server object and my client is same. So If those two are different, How can I access the server object.
I tried with my another computer IP
as
tcp://200.100.0.52:1234//TestRemoting
that time I am getting an exception as
A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond 200.100.0.52:1234

The message means most of the time that the client cannot find the service. You can use the following steps to determine where the connection fails:
Check if the service is running on the remote machine.
Check if the port number is correct.
Ping the remote machine from the client.
Open a telnet session to the remote machine on the port number of service.
The step on which it fails gives an indication of why it is failing.

No connection could be made because the target machine actively refused it [not similar to others]

I'm trying to learn Socket Programming, and I encountered this error while connecting to my server application.
Here's my declaration of the TcpListener in the server application:
TcpListener listener = new TcpListener(IPAddress.Loopback, 5152);
and here's my declaration of the TcpClient in my client application:
TcpClient client = new TcpClient(Dns.GetHostEntry(IPAddress.Loopback).HostName, 5152);
I have read several questions like this, and I always get the same answer: Either the server application isn't listening to the port or not running at all. But I've double-checked the Resource Monitor and cmd using netstat to see if the service is listening to the port, and it is. I've also included the service in the Firewall exceptions, so I'm not sure why I keep getting this error while trying to connect to the server app.
Any ideas?

Dns.GetHostEntry(IPAddress.Loopback).HostName returns the host name of your machine. When you pass a host name to TcpClient, it will resolve it to one or more IP addresses using Dns.GetHostAddresses(hostName). This includes the public and link-local IP addresses of your machine (e.g., 192.168.15.4), but not the loopback address (127.0.0.1).
So your client is trying to connect to any of the non-loopback addresses of your machine, while your server is listening only on the loopback address. Thus, no connection can be established.
Solution: Connect to the same end point your server is listening on.
IPEndPoint endPoint = new IPEndPoint(IPAddress.Loopback, 5152);
TcpListener listener = new TcpListener(endPoint);
TcpClient client = new TcpClient();
client.Connect(endPoint);

Sending a file to a Dynamic port by a TCP Protocol

I am working with an application that receives a file by a TCP protocol, the application processes the file and then sends it by the same protocol, i am receiving the file without problems, my problem is when i try to send the file, because i need to send the file to another application that is listening a Dynamic port, the code that i am using to send these files is:
internal void Send(byte[] buffer)
{
TcpClient _client = null;
try
{
_client = new TcpClient(RemoteIPaddress, Dynamic_port);
if (_client != null)
{
NetworkStream _clienttStream = _client.GetStream();
_clienttStream.Write(buffer, 0, buffer.Length);
_clienttStream.Flush();
_clienttStream.Close();
_clienttStream = null;
}
}
catch
{
if (_client != null)
{
_client.Close();
_client = null;
}
}
}
The question is, how can i send a file by TCP protocol to a remote machine that uses a dynamic port

Typically, the server should listen on a well known port for a connection request. The response should include the port number that the server will communicate further on. Then your app connects to that port for transferring the data.
The communication should do the following:
Client connects to server on well known port.
Server responds with the dynamic port number to use for further communication.
Client connects to server on the received port number.
Server responds stating connection established.
Client transmits data and disconnects.
This is a simplified version of how passive FTP works.
Point is, there are only two ways to connect to a server on a dynamic port. The first way is outlined above. If you can't do it that way then your client app will have to do a port scan, sending a connection attempt to every port within a range, and see which one the server responds on. However, firewalls are generally programmed to notice this type of thing and shut you down (it's hacker behavior).

Are you asking how you can determine the dynamic port that the remote machine has selected to use? There is no automated way to do this. The server should either work on a port that both machines are aware of or you should work out a way for them to select a port through some other mode of communication. Either by connecting to a 3rd party server or hosting a web service that the client can access.

Spoof IP address for HTTP web request?

I have a web service on a server in my company that we have restricted access to from all but one other server on our network.
I do however need to make calls to this from another machine. Is there a way I can spoof the other servers IP address in order to send an http request to the web service? I only need to send it info I don't need any returned data. It's for logging hits from another server on our main server.
I am using this
IPEndPoint endpointAddress = new IPEndPoint(IPAddress.Parse(ipAddress), 80);
using (Socket socket = new Socket(endpointAddress.AddressFamily, SocketType.Stream, ProtocolType.Tcp))
{
socket.SendTimeout = 500;
socket.Connect(endpointAddress);
socket.Send(byteGetString, byteGetString.Length, 0);
}
but get an exception
A connection attempt failed because
the connected party did not properly
respond after a period of time, or
established connection failed because
connected host has failed to respond
23.202.147.163:80

In general, it is not possible to establish a TCP connection with a server without being able to receive and process some reply packets from that server. HTTP is built upon TCP, and TCP starts communications with a "3-way handshake" that lets the client and server communicate.
The start of an HTTP request is not a single packet.

You could use a proxy to bounce your requests from an IP address that has access.