Had the same issue. With your router off, try unplugging the power to your cable modem (or DSL) and then give it a few minutes to get a connection re-established. Then power up your router, also giving it a few minutes to establish all connections. If this does not work, several reboots of your router will be needed.
Once online go to dlink and download the latest flash for your router. It should be 1.15. Re-flash the router and you should not have this problem anymore.