D-Link ShareCenter DNS-320L User Manual page 155

Section 4 - Configuration
The window expands to include a Blocked IP list and a FTP Server
Status report. Click the blue arrow to see the drop-down list.
Click New to block a specific IP address.
Select IPv4 or IPv6 and then enter the IP address of a machine
you wish to block. Select Permanent if you wish to block the
IP address permanently or Temporary if you wish to set a time
frame.
If you selected permanent, click Apply and continue.
D-Link ShareCenter DNS-320L User Manual 149