Any updates on Pandora?
Normally it's possible to listen free without credentials for a limited time.To my knowledge i need some credentials.
Before you worry, have you done the most basic step? (Try visiting www.pandora.com in a standard Internet browser and check if you can use the service.) If you can use the service in your browser, the plugin should also be usable. If you get a VPN, that also gives you an independant way to test whether the VPN is working.