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Windows Update Not Working - Workaround

Contributor

Windows Update Not Working - Workaround

Can't access Windows Update on my desktop (10 Pro, v10.0.17763.292) or my laptop (10 Home).

Get error message: "Can't connect right now - try later or check your internet connectivity"

 

What I tried that did not work:

Reset and reregistered Windows Update

Ran Windows Update Troubleshooter

A clean install of Windows 10

 

What I finally found that did work and allowed me to fetch the latest Windows 10 Updates:

Changed my IPV 4 and IPV6 DNS lookups from Comcast default DNS to Google Public DNS: Google Public DNS

 

This problem is repeatable by changing back to Comcast default DNS lookups.

 

Hopefully, Comcast will fix this issue.

New Poster

Re: Windows Update Not Working - Solved

Agreed, changing your DNS to Google's or to a VPN should not be a long-term solution. Really hope Comcast works on fixing this issue.

Highlighted
Silver Problem Solver

Re: Windows Update Not Working - Solved

I think the original poster should change the subject from "Solved" to "Workaround", as Solved implies Comcast has fixed their DNS.

New Poster

Re: Windows Update Not Working - Workaround

Agreed.  Same problem with Windows Update since yesterday; Comcast DNS servers do not succeed in reaching Windows Update.  I also changed to Google Public DNS servers, and the WU connection succeeded within 5 seconds, and continues to work as of about 5 minutes ago.

 

It's also worth noting, though, that before trying Google Public DNS, I tried another set of free DNS servers (Cloudflare), and they couldn't connect to WU either.  So while Comcast is definitely affected by this problem, it seems it's not entirely Comcast's fault.  I think it will take Comcast working on this, with or without collaboration with MS, to get this sorted out.

 

Best of luck on this to everyone!

Contributor

Re: Windows Update Not Working - Workaround


@LWeissert wrote:

Agreed.  Same problem with Windows Update since yesterday; Comcast DNS servers do not succeed in reaching Windows Update.  I also changed to Google Public DNS servers, and the WU connection succeeded within 5 seconds, and continues to work as of about 5 minutes ago.

 

It's also worth noting, though, that before trying Google Public DNS, I tried another set of free DNS servers (Cloudflare), and they couldn't connect to WU either.  So while Comcast is definitely affected by this problem, it seems it's not entirely Comcast's fault.  I think it will take Comcast working on this, with or without collaboration with MS, to get this sorted out.

 

Best of luck on this to everyone!


I believe both Cloudflare and Comcast are at fault. Apparently, some DNS change is/was required, and neither updated thier DNS routing tables. In the past, I have noticed that some DNS servers get updated (almost) immediately upon notification of a routing change, while others take days, weeks, even months to make the same change. Now what was the required change? Who knows?

 

Also, this change to Google Public DNS fixed Defender Smartscreen Scanning and the Windows Store Apps are now updating again too.

 

Cheers!

Silver Problem Solver

Re: Windows Update Not Working - Workaround

The issue appears to be fixed and Comcast's DNS is properly resolving the address.

Contributor

Re: Windows Update Not Working - Workaround


@andyross wrote:

The issue appears to be fixed and Comcast's DNS is properly resolving the address.


Thanks for that heads up! However, I wonder if Comcast has more than one DNS routing array (because of thier large footprint) and, if so, have all been updated?

 

I spent an entire night troubleshooting this issue so I am not willing to revert to Comcast DNS routing at this time but it would be nice to know if anyone else was broken and now is fixed? 

Expert

Re: Windows Update Not Working - Workaround

@NJGroundHog wrote:

 

Thanks for that heads up! However, I wonder if Comcast has more than one DNS routing array (becase of thier large footprint) and, if so, have all been updated?


Yes, they do. *Anycast* is being used.



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Silver Problem Solver

Re: Windows Update Not Working - Workaround

You can do a "tracert 75.75.75.75" (or other Comcast DNS) to see where you end up, I think. For the Chicago area, I get cdns01.comcast.net, which is in Chicago's area4. 75.75.76.76 goes to cdns02, which seems to be in Northlake.

Expert

Re: Windows Update Not Working - Workaround


@andyross wrote:

You can do a "tracert 75.75.75.75" (or other Comcast DNS) to see where you end up, I think. For the Chicago area, I get cdns01.comcast.net, which is in Chicago's area4. 75.75.76.76 goes to cdns02, which seems to be in Northlake.


Seems that my cdns01 is quite local to me;

 

C:\Users\upsan>tracert 75.75.75.75

Tracing route to cdns01.comcast.net [75.75.75.75]
over a maximum of 30 hops:

 

1 2 ms 2 ms 1 ms 192.168.1.1
2 11 ms 11 ms 13 ms 96.120.73.93
3 17 ms 10 ms 11 ms 68.85.119.97
4 13 ms 14 ms 12 ms be-37-ar03.eastwindsor.nj.panjde.comcast.net [162.151.210.109]
5 14 ms 16 ms 14 ms be-300-ar03.audubon.nj.panjde.comcast.net [68.85.62.213]
6 17 ms 17 ms 17 ms hu-0-0-0-0-ur01-v.emersonln.nj.panjde.comcast.net [68.85.35.206]
7 14 ms 14 ms 17 ms dns-sw01.emersonln.nj.panjde.comcast.net [68.86.221.150]
8 14 ms 16 ms 15 ms cdns01.comcast.net [75.75.75.75]

 

Trace complete.

 

You can't just go by the hostnames of cdns.comcast.net 01 / 02.



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I am a Customer Expert volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark the post as Best Answer!
Silver Problem Solver

Re: Windows Update Not Working - Workaround

Yes. It looks like you need to use the last hop before the server to guesstimate where it is.