Need fix "An existing connection was forcibly closed by the remote host"

I am trying to develope Win application but i get some issues i have tried a lot to solve them by (googled) and all solutions fail to fix

First issue: i get this state in some situation.

System.Net.Sockets.SocketException (0x80004005): An existing connection was forcibly closed by the remote host at System.Net.Sockets.Socket.Receive(Byte[] buffer, Int32 offset, Int32 size, SocketFlags socketFlags) at System.Net.Sockets.Socket.Receive(Byte[] buffer) at AlphaTesterApp.Tester.MainTest.proc_Click() in C:\path\file.cs:line 101

Second issue: i get this state in some situation

Refused to connect

Please help to fix them(i spent three weeks to fix them without give up).

Edit: i find that issues occure because Delay (if delay more 2 sec i get "An existing connection was forcibly closed") . the cause of delay is slow of internet.

if anyone has solution to fix that i will be very happy