2 pcs are atached to the network and I'll try updating the drivers and let you know if it works.Wireless or ethernet cable? How many pc's attached to the network? Do you have the latest driver installed for the network card you are using?
Unpluging won't work and I'll try updating my drivers.make sure you have the latest wifi adapter drivers and also might want to reset (unplug for a minute than plug back in) your router.