When entering a WPA key in the network settings of

When you enter the WPA key, use the appropriate key on number keypad on the front panel. Keep pressing the appropriate key until the desired letter (upper or lower) appears.

Once the correct letter is displayed, wait a second or two and the cursor will move to right so you can enter the next letter or key.

A second option is to connect the printer to your using the wired connection and then open the web interface using the ip address of the printer. Login to the printer then go to the wireless security settings and enter the Pre-Shared Key (WPA key).

It's also a good idea to put a check mark in the "Obscure PSK" option box as an added security measure.