diff --git a/TestProtocol/CustomServer.cs b/TestProtocol/CustomServer.cs
index 1c762ab..f5c6af0 100644
--- a/TestProtocol/CustomServer.cs
+++ b/TestProtocol/CustomServer.cs
@@ -63,6 +63,8 @@ namespace TestProtocol
                 return;
             }
 
+            this.running = false;
+
             this.serverSocket.Close();
 
             if( this.readSocket != null )