error message 'no internet connection'

my laptop works fine with spotify but my main computer (windows, no network, bt braodband) keeps saying I have no internet connection. However I do have an internet connection. I've uninstalled and reinstalled spotify software twice now but it still doesn't connect and won't let me log on. I know my log on details etc are correct as they log on through my lap top. It used to work fine and I haven't upgraded /changed my firewall settings.