I have been running Windows 7 on my desktop for about 2 months, with no real problems. This compuer is connected to a Linksys router, which is connected to a cable modem. I have onenotebook running XP accessing the network via the router.Yesterday I triedadding a new notebook running Vista, and was having trouble getting the router to recognice it. I looked around the networking areas on my desktop, but I do not believe that I changed anything. After a while, I noticedthe Vista notebook was now connected, but I can no longer connect via my desktop. Diagnostics state "There doesn'appear to be a problem with your connection but Windows can't reach the remote computer."Last night I talked to my ISP and Linksys tech support. I can connect when hardwired to the modem, so network card appears to be working properly. Both notebooks are still connecting fine. Trying to connect to the router via the router's default IP address does not work.Any suggestions before I give up on Windows 7?

Check your router. You will have to login to your router from one of the working computers. What you are probably experiencing is that your router is set to only issue out a certain number of IP address and you are now starting to exceed that number. If your router is wireless, this also suggests that you have not locked it down. For example, the default setting for some routers is to only issue out about 10 IP addresses. If you have three home computers, then that leaves you with seven more available addresses. However, if you have wireless turned on and has not protected it with WPA, you may be sharing your router with some of your neighbors (I see it happen all the time). Now, with an unsecured router in which anyone can connect, not only did your router issue out the three IP addresses to your home computers, but it could have also issued out the remaining seven to those looking to get a free ride. When you decided to add a fourth computer, it will have problems getting a valid IP address and subsequently it will have just a much trouble connecting to any network services. From what you have typed, you may need to double-check your router settings. This is not a Windows 7 problem.