D-Link DWR-512 User Manual page 77

Section 4 - Connecting to a Wireless Network
3. The Wireless Network Connection box will appear. Enter the WPA-PSK
passphrase and click Connect.
It may take 20-30 seconds to connect to the wireless network. If the connection
fails, please verify that the WPA-PSK settings are correct. The WPA-PSK
passphrase must be exactly the same as on the wireless router.
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