My idea, but not sure about it:The integrated network card just ain't good enough which causes GW2 to believe you have an internet failure. It is a more common problem with newer laptops and games that require constant internet connection. Most common solutions: attach a LAN cable or simply get an external wifi receiver as suggested above. (get a good brand and at least an N-receiver preferrably dual band, if your router supports it I'd even suggest to take an 802.11ac one)