Mystery open network

Question

I'm using an airport extreme as an access point with two windows computers.  I set up only one network and made it secure.  But windows is listing a second network, which is not secured, called Apple Network x2c986 (characters changed for security purposes). This open network is not listed in the airport utility. I'd like to know what it is and how to secure it.
My network is physically configured like this:
cable modem <-> apple airport extreme (ethernet).
AAE <-> WinXP laptop (ethernet)
AAE <->WinXP laptop <-> Windows 7 laptop (wireless)
The secure network has wpa2-personal security, aes encryption and a security key. The Apple network has none of these. I can apply wpa2-personal security, aes encryption and the security key in the Windows securitiy properties window, but  what am I securing and can doing so mess up my network?
Thanks for any help.
Ellen

Answer 1

But windows is listing a second network, which is not secured, called Apple Network x2c986
This is one of two things:
1) Another user near you has an Apple device that they have not set up yet. Normally, you would "see" the device in AirPort Utility if you connect to the network.  Is that the case? Can you connect to this network?  If yes, best to leave well enough alone. Someone is foolish enough to leave their network open and use default names for their network.
2) Apple routers use the Apple Network xxxxxx network name to set up the device using wireless. This might have been your AirPort device and the computer is "remembering" the old previous connection. If you try to connect to the this network, but nothing happens, then this is the default network that your device produced before you configured it.