Member Avatar for maz1955

I can access any site except or www.att.net. I have Verizon DSL. AT&T claims it is my firewall/DSL provider blocking my access. I installed nothing new on my PC and all of a sudden I can't get to those two sites. I ran a trace route from my router to both sites and they were successful. So I'm at a loss as to why else to try.

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  • Latest Post Latest Post by happyguy142

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Short summary and targeted next steps tied to the existing troubleshooting: already shows the router can reach the AT&T hosts (traceroute) and has cleared the DNS cache, while ’s DNS-swap suggestion is on the right track. Because the path to the host appears reachable but the browser reports “page cannot be displayed,” the problem is most likely at the client/application layer (hosts/proxy/firewall), the router’s DNS/proxy behavior, or an ISP-level HTTP/blocking issue rather than basic IP routing.

Practical, ordered checks (each step adds diagnostic detail):

  1. Verify name resolution locally and against an external resolver:

    nslookup www.att.net
nslookup www.att.net 8.8.8.8

    Compare answers. Different or missing responses point to DNS caching/forwarding problems.

  2. Confirm no local host override or system proxy:

    notepad C:\Windows\System32\drivers\etc\hosts
netsh winhttp show proxy

    Remove any att.* entries from the hosts file. Ensure no system proxy is set.

  3. Test raw TCP connectivity to the web port (confirms whether HTTP handshakes get through):

    telnet www.att.net 80

    (or, on modern Windows: Test-NetConnection -ComputerName www.att.net -Port 80). No TCP connect or immediate RST/ICMP indicates filtering.

  4. Isolate the scope: try a different device on the same LAN, and try the same site from a different network (mobile tether or remote web checker). If other networks can reach the site but the LAN cannot, the issue is on the local path/ISP.

  5. Temporarily disable third-party firewall/antivirus and reboot the router. If the stack looks corrupted, a Winsock reset can be tried:

    netsh winsock reset

    (requires reboot).

If low-level tests show SYNs are sent but no SYN-ACK returns (or RSTs arrive), capture a short packet trace with Wireshark and escalate to the ISP with the trace, traceroute, and DNS lookup outputs. Those artifacts let support determine whether the block is on the ISP/peering side or inside the local network.

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Member Avatar for happyguy142

could try some little things like flushing dns and the such. What happens when you go to those sites? do they just say "page cannot be displayed"?

Member Avatar for maz1955

could try some little things like flushing dns and the such. What happens when you go to those sites? do they just say "page cannot be displayed"?

Yes, I get page cannot be displayed. Tried ipconfig /flushdns with no success. I've checked all the obvious in IE options.

Member Avatar for happyguy142

Just for giggles, try giving your self a static dns. Good one to use is google's dns. and 8.8.4.4. If you are unsure how to do that let me know what os you are running.

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