In order to connect to the Access Point, you must first configure the TCP/IPv4 connection of your Mac OS/X computer system. (Unless it already has an IP in the same subnet.)
Step 1: Go to System Preferences (Which can be opened in the Applications folder or selecting it in the Apple Menu).
Step 2: Select Network in the Internet & Network section.
Step 3: Highlight Ethernet.
Step 4: In Configure IPv4, select Manually.
Step 5: Enter enter an IP address that is different from the Access Point, but in the same subnet and enter the same subnet mask then press OK.
For example: ENH220EXT IP address: 192.168.1.1
PC IP address: 192.168.1.10 (or any free IP in the range from 192.168.1.2 up to and including 192.168.1.254).
PC Subnet mask: 255.255.255.0
Step 6: Click Apply when done