hi everrybody there are regularly two networks around my computer, one is my own (- stronger) and one is a neifghbour's (-less strong). i keep on setting airport to preferred networks thru system prferences and putting my network at the top and deleting the other network, then i lock the changes, but the computer always seems to add the other network by itself and then connerct to its weaker signal every time i boot up/ wake up. is there anything i can do to ensure my neowrk will always be the one io want it to?