Currently Being ModeratedAug 14, 2013 6:54 AM (in response to David_1)
wifi communication requires part of the Itunes services to be "ON". Particularly Bonjour service. Something shutting down or suspending service would be the reason why. It may be your windows or their firewall, or your antivirus. You can try to eliminate what it is by temporary disabling those and checking if problem still exists.