W5100 webclient problem on specific network

hello,

i have function code web client works without problem on network @ home. when move network in work works, momentary jams.
every second reading simple web page, , listing contents serial.
in network becomes in 5-60 seconds connection failed in step:

if (client.connect(server, 80)) {
   // serial.println("connected");
    client.println(text);
    client.println("host: ____server_____");
    client.println();
   client.println("connection: close");
    return readpage();
  }else{
      serial.println("connection failed");

arduino stopped 15 seconds, before continuing in loop.
ping server , arduino seems without problems , network stable ..
has seen this?
thanks advice

a snippet not enough determine problem. post code. user code tags.

Arduino Forum > Using Arduino > Networking, Protocols, and Devices (Moderator: fabioc84) > W5100 webclient problem on specific network

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