D-Link DWA-556 User Manual page 35

Section 4 - Wireless Security
3. Enter the same security key or passphrase that is on your router and
click Connect.
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.
D-Link DWA-556 User Manual 35