D-Link DWR-921 User Manual page 76

Section 4 - Connecting to a Wireless Network
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.
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