57D-Link GO-RT-N300 User Manual
Section 5 - Connecting to a Wireless Network
5. Enter the same security key or passphrase that is on your router 
and  click  Connect. You can  also  connect  by  pushing  the WPS 
button on the router.
It may take 20-30 seconds to connect to the wireless network. If the 
connection fails, please verify that the security settings are correct. 
The key or passphrase must be exactly the same as on the wireless 
router.