So... my sister owns a Macbook (fall 2008 edition), and over the last 6-12 months it has been having issues connecting to wireless. At first, it would seem to work at some locations (i.e. home, school) but not others (i.e. apartment). So at first we figured it was just the router in those locations that is was not working. However, over the last several months, it's gradually been having trouble at more and more spots (that had previously worked) and now it seems to not work at all. For example, it will be connected but then over the course of an hour, it will lose connection multiple times and we have to turn off/on Wi-Fi for it to re-find the signal. Still other times, it will see the signal, and we will click to connect, and it will sit there for a minute like it's trying to connect, and then eventually will not be able to. For all of these instances, there are other devices that work perfectly well with the connection, so we have narrowed it down to the computer. Wired ethernet connections work fine. But is there some test or anything we can do to further diagnose the problem, short of taking it to the Apple Store? My only guess is that it could be a faulty wireless card, but I have never had similar issues, so my experience is very limited. Does anyone have any possible recommendations for what we can do to identify the problem or remedies? Thanks!