C # re-read from socket

I am trying to read from a socket for the first time and then interrupt the thread that is processing it and then re-read again. The weird part here is that sometimes it works and sometimes it doesn't.

customer:

private void startSend() 
{
    Image f;
    ms = new MemoryStream();
    while (true) 
    {
        f = GetDesktopImage();
        f.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);
        bmpBytes = (ms.ToArray());
        SendVarData(client.Client, bmpBytes);
        count++;
        ms.SetLength(0);
    }
}

private int SendVarData(Socket s, byte[] data) 
{
    total = 0;
    int size = data.Length;
    int dataleft = size;
    int sent;

    datasize = BitConverter.GetBytes(size);
    sent = s.Send(datasize);

    while (total < size) 
    {
        sent = s.Send(data, total, dataleft, SocketFlags.None);
        total += sent;
        dataleft -= sent;
    }
    return total;
}

      

        
        
        
      

    

I am calling start dispatch on a thread that is always running in the background.

server code:

MemoryStream ms;
byte[] data;
public void startListening() 
{
    while (true) 
    {
        try 
        {
            data = ReceiveVarData(client.Client);
            ms = new MemoryStream(data);
            theImage.Image = Image.FromStream(ms);
            count++;
        } catch {}
    }
}

private static byte[] ReceiveVarData(Socket s) 
{
    int total = 0;
    int recv;
    byte[] datasize = new byte[4];

    recv = s.Receive(datasize, 0, 4, 0);
    int size = BitConverter.ToInt32(datasize, 0);
    int dataleft = size;
    byte[] data = new byte[size];

    while (total < size) 
    {
        recv = s.Receive(data, total, dataleft, 0);
        if (recv == 0) break;
        total += recv;
        dataleft -= recv;
    }
    return data;
}

      

        
        
        
      

    

It works fine as I said the first time, but than when I try to close the stream on the second form, close

private void Window_Closing(object sender, System.ComponentModel.CancelEventArgs e)
{
    th.Abort();
}

      

        
        
        
      

    

and try reading again. I just get an error on this line

byte [] data = new byte [size];

Mistake:

Arithmetic operation overflowed

tried to print the value size

and it was something like -2522561418

...

of course i restart the thread again when i open the form

th= new Thread(new ThreadStart(startListening));
th.Start();