Why do think you have an intruder-what's the evidence?
Does this intruder show up in the Network page in the router configuration?
This program will tell you what machines are active on your network:
http://www.lookatlan.com/download_lal.html
hughv
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Yes, but are they current, especially since you've installed security?
This often happens inadvertently, also. I have accidentally connected to my neighbor's wi fi from time to time, so these may not be "intruders" at all, just accidental travellers.
Refresh your network map and see who's there now.
If they are, you can set up MAC filtering, but remember that neither filtering nor WEP are rigorous.
hughv
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