Member Avatar for Nakusya

Hi,
My colleague and I have a strange issue where certain sites give us a "DNS error - cannot find server" error. We share an office with a friend and his PC, connected to the same router is able to view all these options without any issues whatsoever.

I ping the sites and they dont exist. Some sites were visible and arent now. Its the same with Firefox, IE7 and Chrome.

I have quite a few firefox plugins including Xmarks as well as Dropbox installed. I did have Kaspersky 2009 installed but someone told me to uninstall it to fix the issue which I did. Unfortunately I cant find the disc so have installed AVG for the time being. I have also removed Xmarks but still get the same issues.

Any help gratefully appreciated

Regards

nakusya

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  • Latest Post Latest Post by MidiMagic

Dani AI

Generated

A few diagnostic points based on the thread: ’s Winsock suggestion and the router power‑cycle were reasonable first steps, and ’s ISP check is worth keeping in mind. The key clues are that the affected machine resolves sites correctly when using a 3G dongle and that a different PC on the same router has no problem. That pattern strongly points to the affected PC’s resolver/configuration or a leftover network filter from removed security software rather than a site outage or a general ISP block.

A concise diagnostic sequence (run from an elevated Command Prompt) will isolate the cause:

ipconfig /all
ipconfig /flushdns
ipconfig /release
ipconfig /renew
nslookup example.com
nslookup example.com 8.8.8.8
ping 8.8.8.8

Interpretation notes: ipconfig /all shows the active DNS server(s). If nslookup against a public DNS (8.8.8.8) succeeds while the default lookup fails, the problem is the configured DNS resolver on that machine (or the router’s DNS forwarder). A default server of 127.0.0.1 indicates a local DNS proxy/filter. Successful pings to 8.8.8.8 confirm basic IP connectivity.

Additional checks and practical fixes: inspect the hosts file at C:\Windows\System32\drivers\etc\hosts for unwanted entries; verify that no proxy is set (Internet Options -> Connections -> LAN Settings and Firefox/Chrome network settings); review the network adapter Properties for leftover AV/Kaspersky filter drivers or components and remove or disable them (vendor removal tools are often required to clear remnants). Booting into Safe Mode with Networking or performing a clean boot (msconfig: disable non‑Microsoft services/startup) helps reveal third‑party interference. As a test, temporarily set the adapter’s DNS to a public server (8.8.8.8 or 1.1.1.1); success there confirms a local resolver/router issue.

If these steps still leave some domains failing while others work, compare the full ipconfig /all outputs between the working and failing machines and consider a network stack reset (netsh int ip reset and netsh winsock reset) or reinstalling the network adapter driver.

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Member Avatar for Nakusya

Download and run Winsockfix from here http://www.softpedia.com/get/Tweak/Network-Tweak/WinSockFix.shtml
Reboot and see if that helped.

Hi,

I installed WinSockFix and rebooted and it didnt help :(

I also disconnected the cable to the router and inserted a 3G dongle and I could view all sites perfectly on the same PC that wasnt letting me before

Not sure how to proceed from here now

Any help gratefully accepted

Regards

Nakusya

Member Avatar for crunchie

Have you tried recycling the power on the modem/router?
If not, try that and see if it helps.

Member Avatar for Nakusya

Have you tried recycling the power on the modem/router?
If not, try that and see if it helps.

Hi,

Thanks for this - I powered off our PCs, powered off the router, waited 5 minutes, powered the router back up then powered up the PCs and I still have the same issue

Pulling my hair out here!

Regards

Nakusya

Member Avatar for MidiMagic

Has your service provider blocked these sites for some reason?

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