Can someone please tell me how often it pops up that message about the network being insecure? Is it just once each time the computer connects to the network, or every few minutes, or what frequency?

Please note, programmers, I believe it is not always bad not to have a password on the wireless network. I have a very short range, and I am in a rural area where the nearest neighbor is two miles away. If you know of another reason that I should have a password on the network, please inform me. Thank you for your time.