TCPClient hangs up core

Troubleshooting
27

Hi Zach,

I started out with trying to amend and use this code: http://arduino.cc/en/Tutorial/WebServer

I have now tried this shorter code to try to eliminate any sources of error, but still the same result. I typically get a response on the first attempts, and then no response before I restart the core (power off / power on).

TCPServer server = TCPServer(80);

void setup()
{
server.begin();
}

void loop()
{
TCPClient client = server.available();
if (client) {
delay(50);
client.println("HTTP/1.1 200 OK");
client.println("Content-Type: text/html");
client.println("Connection: close");
client.println("Refresh: 5");
client.println();
client.println("< !DOCTYPE HTML>");
client.println("< html>");
client.println("Hello world...?");
client.println("< /html>");
delay(50);
client.stop();
}
}

Using a terminal on port 80 gives me a answer on the first attempt:

telnet 192.168.1.13 80
Trying 192.168.1.13...
Connected to 192.168.1.13.
Escape character is '^]'.

HTTP/1.1 200 OK
Content-Type: text/html
Connection: close
Refresh: 5

< html>
Hello world...
< /html>
Connection closed by foreign host.

And after that nothing happens:

Trying 192.168.1.13...
Connected to 192.168.1.13.
Escape character is '^]'.
Connection closed by foreign host.

I have no clue whether I am doing anything wrong, or what this can be. Any help would be highly appreciated.