I have my imac set so that the only preferred network on the list, is the one we have coming from our airport extreme base station. Since the firmware update, the imac seems to forget to connect to this when it starts up, and says "none of your preferred networks were found, would you like to connect to -----?" I then click on the airport menu icon and my network is in the list. Why is it doing this? Also, windows xp pro forgets the time of the day upon every boot up.