In your wireless router configuration, you should be able to set it to allow connections only from wireless client devices with the MAC addresses you specify - and you would specify only the addresses of your two computers. Then, no other wireless devices would be allowed to connect.
I'm guessing here that a neighbor of yours has a wireless computer/router and somehow it keeps detecting your router's signal and then attempting to connect. Although you've changed your router's setting to not broadcast the SSID, if a wireless client already "knows" the SSID (which might be possible from a while ago before you discovered this problem and turned off the SSID broadcast) it will still attempt to connect and your router will still accept incoming traffic from a client that demonstrates potential friendliness by already knowing the router's name. Then you have to depend on the WEP key for restricting access. You might try changing the SSID, but that also means reconfiguring your computers to access the new SSID.
Finally, if this is all unintentional interference between your wireless and your neighbor's, you might try changing the channel of your network. If that doesn't work, you'll have to determine which neighbor is being unneighborly and work with them. For that, it might be as simple as turning your router off, then walk around the house with your laptop (the one with XP) trying to detect signals. If you find a signal that is stronger on one side of the house than the other, go visit the neighbor on that side and have a friendly tech-chat about how he can improve the quality of his internet experience (i.e., the stability of his connection) by not trying to reconnect to yours every few minutes...
dw
When web surfing wirelessly, every ten minutes or so, I get a firewall warning that a neighboring devise was connected to my wireless router, and I have a choice to click it as: "Trusted" or "Not Trusted". Even after clicking it as "Not Trusted" everytime, this warning keeps appearing everyday. The warning stated the devise as a router but the computer name has only a dash.
I have already done the following security measures:
1. use a unique SSID
2. not broadcast the SSID
3. changed the router's default password
4. use WEP (my laptop built-in wifi does not have WPA)
5. config in router only my 2 laptops as "Trusted" access to the router
6. Have a firewall in my TrendMicro antivirus
This problem happens in my 2 laptops, one with W2KSP4, the other XP-Home-sp2.
Any advice on how to resolve this would be greatly appreciated.
Thanks in advance.

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