D-Link Air DCF-660W/K Manual page 12

IP Address
When assigning IP Addresses to the computers on the network, please
remember that the IP Address for each computer must be in the same IP
Address range as all the computers in the network, and the subnet mask
must be exactly the same for all the computers in the network.
For example: If the first computer is assigned an IP Address of 192.168.0.2
with a Subnet Mask of 255.255.255.0, then the second computer can be
assigned an IP Address of 192.168.0.3 with a Subnet Mask of 255.255.255.0,
etc.
IMPORTANT: If computers or other devices are assigned the same IP
Address, one or more of the devices may not be visible on the network.
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