Have been using Windows 7 for six months with no problem. Computer is connected via ethernet cables to a Linksys router than to TimeWarner modem There are six computers on this network, three ethernet linked, three wireless, all other computers are working fine. Problem computer error is "local area connection" doesn't have a valid IP configuration. Occasionally is will say the cable is unplugged or not working. Cable has been checked and it is fine. I do not have Bonjour on this computer -- at least I cannot find it or the system string mentioned anywhere. I have tried disabling and then enabling the local area connection -- no luck. I tried renewing the IP address but that didn't work. I did try putting in a static IP address, but I may have done that wrong as I messed up the entire system and I had to reset the router. I did reset the computer back to a previous set point, didn't help. I can't try the other suggested fixes because I cannot get it to connect at all. (I am writing this on a different computer). It says the active network is an unidentified pulbic network. I have done ipconfig /all and the ip adddress it has is 169.254.245.25 which is incorrect, it should be a 192.168 address. I could try the static IP address again if that seems like the solution, but I need to have know how to do this correctly so I don't muck up the entire system.

This could be some type of corruption of the drivers or TCP/IP stack. Not sure what your level of knowledge is regarding supporting Windows 7 systems, but here are some things you can do to troubleshoot this: 1) look at the system log (in event viewer) for possible clues 2) run packet capturing software on the network to see if DHCP broadcast packets are seen on the wire 3) on your Linksys router, are there any events logged that may provide additional clues. Sometimes, these types of issues are easily resolved by going to device manager, uninstalling the NIC, refreshing, and allowing the computer to re-install the hardware (logically of course). On a side note, you shouldn't have to configure a static IP address on this workstation. The 169.254.x.x address is an APIPA IP. Here is some information in case you are interested in reading more about it. Automatic Private IP Addressing (APIPA) http://www.anitkb.com/2010/03/automatic-private-ip-addressing-apipa.html Visit: anITKB.com, an IT Knowledge Base.

This turned out to be a problem with the switchbox. It took a lot of trying various configurations before I figured out that was the most likely problem and when I switched it out to a new one everything worked first thing. The switchbox was only two years old, I just didn't think it would fail. Kathy

Kathy, what is a switchbox? DO you mean the router?Rich Why can't I be different and original like everybody else? - Vivian Stanshal