[EDIT: This issue is solved.] I got this problem this morning and have been working on it for a few hours. I did a lot of Googling to see what might be causing it; nothing seems to be working. It's ethernet, not wireless, and I've had 0 network problems for the half a year since I got the computer; suddenly it doesn't work at all. Stuff I've found/tried: -Windows network diagnostics/troubleshooter is, of course, not able to fix it -Neither rolling back drivers nor updating drivers fix it -System restore doesn't fix it -Various ipconfig commands do not fix it -I do not have and never have had the "Bonjour" something service or iTunes installed which seem to have caused this for some people -Stealing various settings from my laptop (which runs XP and works through the same cable) like the IP address, network address, default DNS servers and all other options while it was connected, then trying to use them as static IP etc. on my desktop computer doesn't fix it -Disabling/enabling IPv6 and IPv4 doesn't fix it -Adding a specific registry key per an old Microsoft KB something article for a similar problem in Vista doesn't fix it (I've since removed the key; it was pretty clearly not the same issue, was for people who upgraded from XP to Vista and suddenly got this error message, whereas I've been using Windows 7 for months with no problems until this) -Executing this script through an elevated Powershell command window does nothing: dimeby8 : Change ?Unidentified network? from Public to Work in Windows 7 -Wishing really hard doesn't fix it -Various resets I found through Google like some cmd thing using "netsh" don't do anything Other relevant information: -Although this is the first time I've had network issues with this computer it's not the first time I've had network issues so I made sure to try pinging things. Pinging a domain like google.com doesn't work because it can't find it, but I am pretty sure this is not a DNS issue as pinging an IP address doesn't work either (I get the message "PING: transmit failed. General failure.", something I have never even seen before... all the problems I've had in the past it would just time out or something) -ipconfig /all's listing for "default gateway is blank." Obviously this is an issue. When I tried using static IP etc copied from what it gave my laptop, though, one of the things I brought over was the default gateway, and I still couldn't connect, so I have no idea. I've attached the ipconfig log. -I do not have access to the router as I live in a dorm, but I don't think it's a router issue anyway. Computer connects perfectly for half a year, then stops working, and laptop that I've never used wired internet with can still connect through it? Sounds more like a computer issue to me, but maybe not. I can of course ask them to reset the router, but honestly even if they would I don't know if the dorm heads have any idea what a router is or where it would be. -I am out of ideas. I'm going to be gone for a few hours so during that time I'm going to completely power down my computer and unplug in the hopes that on the slim chance there's anything screwed up hardware-wise that is staying on somehow even through restarts that by the time I get back and plug everything back in it'll have shut off and will be working properly again. This worked for me, like, once, when a monitor wouldn't turn on. This seems a lot more specific though and I do not have high hopes.