Connect a nine-pin, straight-through DB-9 serial cable to the RS-232 serial port on the access point and to the COM port on a computer.Set up a terminal emulator to communicate with the access point. Use the following settings for the terminal emulator connection:
8 data bits
1 stop bit
Xon/Xoff Flow control .If xon/xoff flow control does not work, use no flow control.
You can use either a crossover cable or straight through cable.
Make sure you choose the correct COM port(Whether COM1 or COM2) on the software.
Even then if you are having trouble accessing the device after setting the terminal program , it is possible that the device is not set to the defaults. Click on Restore Default button to restore the default settings. It might help to try different settings, starting with the baud rate.
Reset the access point by holding the Reset button while you unplug and replug the Power.
Try a different power cable.
For more information on the different device models refer the following URLs