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If I run ipconfig /all, in the DNS field it is showing numbers such as fec:0:0:0:ffff::1%1, fec:0:0:0:ffff::2%1 and fec:0:0:0:ffff::3%1. nslookup www.google.com shows some kind of DNS error (lookup not found or similar). What does this mean and how do I fix it?

I haven't changed anything at the computer side. I am supposed to be able to connect to the Internet as soon as I plug in the cable but this day the Internet stopped working for some reason. So when I checked ipconfig I saw those strange values.

This is what ipconfig shows about DNS:

I didn't change anything recently in my system preferences.

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ipv6? –  Khaleel Aug 30 '13 at 4:43
I would look at the network adapter settings and see if IPv6 is on but IPv4 is not. This is DNS related. You should still be able to ping addresses like and In which case, internet is actually working, just not DNS resolution. –  R Hughes Aug 30 '13 at 4:50
Could you please try disabling ipv6 here? –  Khaleel Aug 30 '13 at 4:51
it sounds like there is moregoing on here. The list of things to check will be quite large and we don't have much to go on yet. Try some of the things listed here to start and try to narrow down the problem more. howtogeek.com/126265/… –  R Hughes Aug 30 '13 at 5:03
The DHCP server you are connecting to appears to be handing out IP6 DNS addresses. That's where your strange letters are coming from. –  R Hughes Aug 30 '13 at 5:05

3 Answers 3

You are indeed using IPv6. This is the default address, something like the 169. addresses in IPv4 that Windows uses and indicates that you could not find a DHCP server when your machine requested a new address.

If you do an ipconfig /renew do you pick up a real address? Did you make changes recently to the networking configuration? Is this a home or work network and are other clients on the same network still able to resolve?

Please post the entire contents of ipconfig /all

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I reset the router and switch and that seems to have solved the problem. While it's working, it look s like the DNS is two ipv4 addresses. So now I am sure it has to be ipv4 to be working. –  user13267 Aug 31 '13 at 2:04


You have Hamachi downloaded am I not mistaken? Your looking at the wrong part of the ipconfig! I just figured it out! Scroll up a litttle more to find your actual router config!

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Thanks. Don't know what's up with the downvotes... but it was true in my case –  Brett Jun 11 '14 at 22:03

go to your advanced adapter settings through the network and sharing center. uninstall all protocols, services, and clients. Then, install each group of them in this order: protocol service client

then click 'diagnose'

the issue should resolve itself.

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