Hi, I'm new to MacRumors and I'm almost certain that this isn't the ideal sub-forum for my question but I wasn't able to find a better one so I'm posting it here. Please do suggest somewhere else I can post my question if you feel that I would get better responses (both inside and outside this forum, if allowed). Products used: Apple Airport Extreme Apple Mac Book Air Other Router Other computers We have an Airport Extreme router and some desktop computers in the house. I get internet through a fiber-optic cable (I just have to plug the LAN cable into my router and I'm good to go). So, the airport extreme provides internet for the desktops in the house. I have a mac book air and I live on the top floor of the house. The airport extreme doesn't transmit its signal all the way to the top floor so I bought a second router (random Netgear router) for the top floor and I connected it to the airport using a LAN cable. So far so good. I now have internet on the top floor because I can use my mac book air to connect to the Netgear router. Now comes the weird problem that I began to face. When I bring my mac book downstairs and I connect it to the airport extreme, I can't connect to the internet. I can connect to the router and all but not to the internet. If I try to use the AirPort utility it says "This airport extreme is already set up and is not reporting any problems." WTF? How is it that I can connect to the same internet connection through the Netgear router upstairs (which is itself connected through the airport) but I can't connect to the internet through the airport extreme downstairs? So, I realize that an obvious solution to my problem is to simply reconfigure the Airport Extreme but that wouldn't help me to discover the source of the problem and the problem may just recur. (In fact, if I didn't have the other desktops at home and the macbook was my only way of using the internet, then I would have thought myself to be 100% sure that the problem lies with the airport and not with the macbook. However, since I can see that the airport is providing internet access to the other desktops, I'm able to see that the problem lies with the macbook rather than the airport). I think that this problem may have something to do with conflicting IP addresses but I'm really quite uneducated in these matters. I once saw a notification on my mac book saying that there was some IP conflict. Any suggestions? ---------- EDIT: And it gets even more weird... I said in the above post that I get internet through a LAN cable that I have to plug into my airport extreme. (ISP called Beam Cable in Hyderabad, India) I actually have two internet connections at home. The second internet connection is an ADSL connection for which I have a D-Link ADSL router. Presently the desktops in my house are able to connect to the D-Link router and connect to the internet through that but my mac book air is unable to connect to the internet through the D-Link router. Again (like the airport problem), the mac book air is connecting to the D-link router but it is unable to connect to the internet. This whole problem just started today. Until yesterday, I was able to use my mac book air to connect to the internet using any of the three routers in the house (Airport, Netgear and D-Link). Today, I am able to connect to all the routers from my mac book air but can reach the internet only through one of the three routers (Netgear).