Yet Another Airport Extreme Setup Question

I have my Airport Extreme set up with both computers on my network connected via ethernet cables. I wanted to test connecting a computer to the network wirelessly, because I will need to connect other devices (e.g., satellite TV receiver, iPhone) wirelessly. But I can’t get the wireless connection to work. First, I click on Network in System Preferences and change the Location to Airport. Then, I select my Airport Extreme network in the drop-down menu for Network Name. A window then opens that says “The network “” requires a WPA password”. I type in the password I entered in the Wireless tab in Airport Utility. This password is directly under the Wireless Security drop-down menu, which is set to “WPA2 Personal” (the default?). After typing in the password, an error message is displayed in the lower left portion of the password window that says “Connection failed”. Is the WPA password something other than the password I entered in the Wireless tab of Airport Utility?