D-Link WA121B1 User Manual page 22

Section 3 - Connecting to a Wireless Network
5. 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-121 User Manual 22