The simplist way would be to perform a "soft" reset on your AirPort Extreme Base Station (AEBS). This type of reset will temporarily disable all of the base station's passwords for up to five minutes. That should give you plenty of time to reset your password using the AirPort Utility.
Thanks Tesserax. Working on the problem right now. I have to say although I think this has me pointed in the right direction, I am finding inaccuracies in the instructions for soft reset using a PC. First of all, the period of time the Airport Extreme is in soft reset mode is nowhere near 5 minutes. I've not put a timer on it, but it has not been adequate time for the process required to actually get in the router during the soft reset timeframe. I would edit the instructions for PC to inform people you need to open Network and Sharing Center and Manage Wireless Networks to disable "automatically sign in to this network" and change the access to the network to open/unencrypted, or just remove the wireless network you are trying to repair from the machine you are using to repair it. Here's why: If the saved wireless network settings for "your_network_name" dictate that it requires a password, during the reset period the network is actually an open network with no security...the setting will not be recognized and you will not be able to use "your_network_name" as it exists on your computer to sign in and use the Airport Utility to change your password. After maybe 2 minutes, the soft reset reverts to the old settings for your router and if you have "automatically sign in to this network" checked for "your_network_name" it will sign back in to the secure profile for that network, and require a password to administer the Airport.
FYI: You cannot create a new network to do this because the Airport retains the name of your network in soft reset, and Windows will not let you have 2 saved networks with the same name but different security settings.
I am going to try this one more time and will first set "automatically connect to this network" unchecked, security settings open/turned off, then I will soft rest the router, and move as fast as I can to change the admin password before it goes back to default settings (NOT 5 minutes...not even close.) If I encounter further frustration, I will be back to post further ranting.