Thanks for the clarification.
To check your AirPort Express from your Mac......
Open Macintosh HD > Applications > Utilities > AirPort Utility
Click on the AirPort Express icon that appears
Click Edit in the smaller window
Click the Wireless tab at the top of the window
Change the setting for Wireless Security to read WPA2 Personal
Enter a password of 8 characters or more than you want to use
Verify the same password
Might be a good idea to write down that password and store it in a safe place
Click the Update button at the lower right of the window
Wait a full minute for the AirPort Express to restart
Now when you want to log onto your wireless network, you will be asked for the password. You should not have to enter the password on subsequent log ins.
