FIbre Support

Get expert support with your Fibre connection.

Showing results for 
Show  only  | Search instead for 
Did you mean: 

Loss of Internet Access

Conversation Starter
Message 21 of 21

In last month our fibre broadband has lost access to the Internet on both wifi or wired connection via our Sagemcom wifi hub.  This results in browser and email services all failing. 


Both Windows Troubleshooter and the Hub's Error Log  identifies the problem as being a DNS failure.


On all occasions:

1.  I have been able to ping TalkTalk's DNS server at with reasonable response times and no packet loss.

2.  Pinging either or results in failure.

3.  Logging into the router and changing the DNS to manual and using alternative Google DNS fixes the problem and Internet access is immediately restored.


There are two things I am not sure about:

1.  Has TalkTalk's DNS server services suffered an outage other than being able to ping the IP address which proves very little, or is the problem actually with the wifi hub and simply changing the DNS IP address to manual clears the problem.

2.  Why does TalkTalk's router and "Service" checker both show that the Internet is available when this problem occurs even though Internet access is most definitely not available.


Anybody got any comments on the above or experiencing similar difficulties and found a solution?


Conversation Starter
Message 1 of 21

Having experienced another couple of apparent DNS failures over the last few days I was wondering if there is any update on the possible cause of the problem and solution.


I haven't put a network monitor on the link yet but am beginning to wonder if this is a timeout issue.  I notice that the 'ping' response time when checking access to DNS immediately after a failure is often  greater than the usual values I see e.g.  30-40ms and sometimes longer vs usual 10-20ms?


Not sure what the router does in terms of timeouts especially when TTL limit is reached but if timeout is a problem then what is the fix?


Conversation Starter
Message 2 of 21

Hi @OCE_Chris 

After a further failure I have tried a factory reset of the routerto see if that helped rather than just resetting the DNS IP addresses.

Sadly it didn't as the router has failed again and had to be reset again.  Have now suffered 6 failures in January and 7 so far in February which is not good suggesting some form of reliability problem.


Windows Event Log identifies failure as "time out" waiting for DNS server response.

Windows Elevated Debug Report identifies "root cause" as default gateway not available


Have included extracts of the above in the attached which might help resolve problem.


Conversation Starter
Message 3 of 21

Hi @Chris-TalkTalk (again)


Just suffered yet another Internet access failure so now twice in one day which is getting problematic.


Once again system reconnected once DNS settings changed to manual and back to auto again.


There does not appear to be any observable rationale for the problem which is sporadic but increasing in frequency.


PC event log again identified DNS as the problem due to timeouts but I am not sure the router Log is capturing the error.


Have inlcuded another screen shot of pings and also router info screen which shows that system is connected so I am not sure just how meaningful that screen is.  I also note that the router states download speed as being 5 to 6 Mbps faster than TalkTalk's own broadband speed check.


Hopefully someone can help sort this quickly.


Message 4 of 21

Didn't know whether to start my own thread or comment here. Having exactly the same problem as jerryf. Same router, same firmware. It's been a problem for over a month now (not sure exactly when it started. Changing the DNS servers fixes the issue for a little while then the same thing (no internet access to all devices) happens again. I'm pretty sure its a Hub issue and not an actual problem with TalkTalk's DNS servers as the issue still occurs after a while regardless of which DNS servers you are using (again, changing to any DNS server other than the one that was in use when the failure occurs fixes the issue). What date was the SG4K10002816t firmware pushed to users? I'm betting that's when the problems started but I could be wrong. It's getting pretty frustrating to be honest, hence my arrival here.


Message 5 of 21

Hi @Chris-TalkTalk 


Update - Replacement Sagemcom Router


Hi again


Have been giving the replacement router plenty of time to settle down and also now connected to a new Win 10 PC.


Initially the new router appeared to suffer fewer failures for the first few weeks but recently has started showing the same problems as the previous unit,  now returned to TalkTalk.


As before symptoms are no Internet access althought logging into router shows that connection is OK.  Changing from auto to manual DNS confiuration or switching router off then on again resolves the problem.  Router is FAST 5364.3.T8 s'ware version SG4K10002816t


I have to say that checking the router's internal log to try and resolve further was disappointing given the inability to search effectively and the date.time structure of the log.  Equally I am not convinced the Log accurately records all failure events.


I have attached a short screen shot showing results of pinging DNS IPs which worked then checking for name resolution of valid URLs which failed.  PC error log reported DNS failure.


I was previously offered a Hauwei unit to check if that resolved this annoying issue but then advised that none were available at the time.  Is it possible to now replace my existing (possibly failing) Sagemcom unit with a Hauwei unit?



Message 6 of 21

Message 7 of 21

Hi @Chris-TalkTalk 


OK will test using replacement Sagemcom over next couple of weeks or so and let you know the results.


Message 8 of 21

Hi jerryf,


I'm sorry, it appears that we're experiencing problems sending Huawei router at the moment. Could you test with the new Sagemcom router just to rule out any hardware issues with the first one



Message 9 of 21

Hi @Michelle-TalkTalk 


Yes, only one router received, the Sagemcom.


Should I be expecting to received a Hauwei unit a well?


Support Team
Message 10 of 21

Hi jerryf,


I'm sorry for the delay. Can I just confirm, has only the one router arrived since your last post?





Conversation Starter
Message 11 of 21

Hi again @Debbie-TalkTalk 

Not sure if the email extract below received 10 Dec is part of reason why Sagemcom rather than Hauwei router was sent but forwarded in case there has been some cross communication:





Hi Jeremy,

It’s important to us that you get the best service possible from TalkTalk. As a thank you for being a loyal TalkTalk customer, we wanted to let you know that we’re upgrading you to our award-winning Wi-Fi Hub (RRP £120), for free!

What you need to know

  • Our delivery company will be in touch in the next few days to let you know when to expect the router.
  • If you need any help installing your new router, we’ve got some handy step by step instructions here.
  • We may require you to return the old router, if so, we’ll be in touch and we’ll send you a returns bag. If you don’t hear from us, please recycle the old router responsibly – see below for details.
  • This is a no strings attached gesture and will not change the terms of our contractual agreement.


This is our best router yet and we hope you enjoy it!

Your TalkTalk Team.

Disposing of your old electronics.

Many electrical devices can be repaired or recycled, meaning they won’t end in landfill causing potential contamination of soil and water. As you’re going to be receiving a new Wi-Fi hub, we want to make sure that your old one gets disposed of according to the Waste Electrical and Electronic Equipment (WEEE) Directive.

You can package up your device along with any cables you don’t need and send it us to recycle for you. Please send this to: WEEE Returns, TalkTalk, 71 Bilton Way, Enfield, EN3 7EP. Or, if you’d rather you can find your local recycling centre at and take it there.

Please do not reply to this email, emails are not monitored.

We’re sending you this email because it contains important information about your TalkTalk service. This is not a marketing email.
© TalkTalk Telecom Limited, Soapworks, Ordsall Lane, Salford, M5 3TT
Registered in England & Wales No. 4633015.




Message 12 of 21

Hi @Debbie-TalkTalk 


Replacement router arrived today.


However, the item delivered is a Sagemcom FAST 5364 unit which is the same as the existing router in use.


I understood that the replacement would be the Hauwei unit to eliminate any Sagemcom related issues.


Has the correct item been sent or did I misunderstand your previous post?


Message 13 of 21

Hi jerryf


The Huawei WIFI Hub is on the way. This is a WIFI Hub like the Sagemcom router it's just a different make and model.


Please allow 24-48hrs for this to arrive. Let us know how the connection compares with this router.






Message 14 of 21

Hi @Michelle-TalkTalk 


Thanks for your reply and yes please send replacement Hauwei hub to see if that resolves the problem.


I assume the Hauwei version supports the same functionality as the Sagemcom variant in terms of connectivity.



Support Team
Message 15 of 21

Hi jerryf,


Thanks for confirming this. Would you like us to send the Huawei wifi hub instead for testing purposes?




Message 16 of 21

Hi @Chris-TalkTalk 


The problem affects all devices on the ntework, both wired and wifi connections.


Symptoms are loss of "connected" icon/symbol on all machines and error message stating particular URL cannot be found, including for email failure.


Can ping with OK results but ping fails to resolve any known URL name (e.g.,,


Windows Troubleshooter and Hub "error" log identify problem as DNS failure.


Logging into Hub and changing DNS from TalkTalk to manual (Google) restores Internet access immediately.  Just switching Hub off then back on again has also restores connection without making any other changes.  Hence I am not sure if the problem is with the Hub or downstream with the DNS service itself.


Failure appears to be random with no obvious cause at this end.




Message 17 of 21

Hi reeferjon,

If you need assistance can you please start your own thread and we'll be happy to help


Support Team
Message 18 of 21

Hi jerryf,


I'm sorry to hear that you've been experiencing problems with your service, have you experienced any further problems since your last post

Do you experience the DNS issue on more than one device?


Conversation Starter
Message 19 of 21

Hi @reeferjon 

It is more than annoying especially as TalkTalk have just sent me an invitation to sign up for another 24 months !


Bit more info - Had another Internet access failure again today and again Troubleshooter identified lack of DNS.  This time rather than logging into Hub ad changing from Automatic to manual DNS at I just turned off the Hub waited 1 minute and then turned on again.  Once the Hub had reconnected all access was restored.  Interestingly unlike previous instances there is no reference to this DNS failure instance in the Hub system log, but it is recorded in the Windows Event Logs.


So still left wondering whether this is a Hub problem or a DNS server problem


Will try and do some more diagnostics next time it occurs but it would be helpful if someone from TalkTalk could confirm the status/reliability of their DNS service.




First Timer
Message 20 of 21

Same issue here over the last 24 hours. Turns out to be a DNS server issue. You can ping them, but try an "nslookup" from the command line on your computer and they won't respond.


I've changed my DNS settings on the router (or the computer) to and's) and the internet connection works find.


I agree it's really annoying that this isn't monitored and reflected on the service status page @jerryf