A network problem I have not seen before ...

[petrusbroder]

On one of my computers the browsers (IE, Firefox, Chrome) and BOINC (software for distributed computing, has been working well for me in all the different versions for a decade) can not communicate with the internet. I have no trouble of reaching the router using any of the browsers, no problems with ping-ing, Windows Network fault solver says that I have internet communication, I can see all the other computers on my network, all the other computers see the "problem computer". The only thing I can not do is browsing the net and using BOINC.
None of the other 9 computers on my intranet have that problem.
This problem occurred after I did a weekly clean-up using the current version of CClean and a registry clean using RegClean Pro - both of which i have used "for ages". I also deleted quite a few programs (image management, office, mediaplayers, etc I have not used for a long time). After deleteing those programs I ran the registry cleaning once more, shut down the computer, and then the problem occurred when the computer restarted.

• Windows 7 Home, all updates current.
• I have scanned the computer for viruses using Windows defender, Malwarebytes, search-and-destroy - no infektion seen.
• I have checked the router and switches - no problems.
• I have reset the router to factory settings, does not solve the problem.
• Windows 7 Firewall off - or on - does not change behavior.
• AVP- on or off - does not change behavior.
• Reinstalling browsers and BOINC - latest version - does not change the behavior.
• Resetting the network properties (control panel) - did no good.
• Switching to WiFi (installing a USB-modem) - did not restore browsing or BOINC-function
• Installing a new network interface card did not restore browsing or BOINC-function

I suspect that the registry clean-up messed up something.
A rollback of the registry changes did not restore ability to browse the net.
The fun part is, that Windows own diagnostics does not see any problem with the internet connection.

I am reluctant to re-install windows or to upgrade to Win 8.1 because that probably means to re-install all my productivity software (office programs, statistics software, video-editing software, image processing software, mail, etc., etc, etc. I do not have a backup of the whole system - that would take some 280 GB (system+programs) + 500GB data. I have a complete and current back-up of all the data on an other computer, so the documents, images, videos, music, etc. are safe and sound, I have checked that. What can I do before I reinstall the system?

 

[VirtualLarry]

Which OS? Have you tried resetting IE settings to factory, and resetting the TCP/IP stack and WinSock?

netsh ip reset c:\log.txt

can you ping www.google.com?

can you nslookup www.google.com?

 

[biodoc]

I agree with VirtualLarry's suggestions

open up a command prompt window.

type: tracert google.com

tracert is windows version of traceroute.

traceroute to google.com from my linux box:

mark@x12-linux ~ $ traceroute google.com

[FONT="Courier New"]traceroute to google.com (173.194.123.7), 30 hops max, 60 byte packets
 1  Wireless_Broadband_Router.home (192.168.1.1)  2.111 ms  2.098 ms  2.087 ms
 2  L100.BSTNMA-VFTTP-106.verizon-gni.net (173.48.139.1)  6.423 ms  9.532 ms  9.525 ms
 3  G0-6-2-0.BSTNMA-LCR-21.verizon-gni.net (130.81.223.48)  9.517 ms  9.507 ms  13.760 ms
 4  ae1-0.BOS-BB-RTR1.verizon-gni.net (130.81.151.60)  39.274 ms  39.273 ms  39.264 ms
 5  0.ae11.XL3.NYC1.ALTER.NET (152.63.20.69)  19.173 ms  21.370 ms  21.364 ms
 6  * * *
 7  2.ae1.XT1.NYC4.ALTER.NET (140.222.228.119)  20.731 ms  19.488 ms 3.ae1.XT1.NYC4.ALTER.NET (140.222.228.121)  16.637 ms
 8  TenGigE0-6-0-6.GW8.NYC4.ALTER.NET (152.63.21.61)  21.944 ms TenGigE0-6-1-0.GW8.NYC4.ALTER.NET (152.63.21.113)  21.940 ms TenGigE0-6-0-0.GW8.NYC4.ALTER.NET (152.63.22.41)  19.444 ms
 9  google-gw.customer.alter.net (152.179.72.62)  19.421 ms  21.614 ms  21.610 ms
10  209.85.255.68 (209.85.255.68)  21.598 ms  19.383 ms  31.932 ms
11  72.14.239.245 (72.14.239.245)  19.365 ms  21.828 ms  20.689 ms
12  lga15s46-in-f7.1e100.net (173.194.123.7)  17.860 ms  17.850 ms  19.841 ms[/FONT]

 

[IndyColtsFan]

It isn't clear to me from your post, but I'm going to assume that you're pinging your gateway and other machines by IP. Similarly, I'm assuming you're browing to your router via IP. If that's the case, it sounds like name resolution might be your problem on this particular PC. To confirm, open your hosts file and add the following entry:

98.139.180.149 www.yahoo.com

Next, see if pinging www.yahoo.com resolves to that IP. If so, open a browser and see if you can now go to www.yahoo.com.

 

[petrusbroder]

Thanks for the suggestions.

Yes, I can ping www.google.com and any IP-adress or any http-address I want
Yes, I can nslookup www.google.com and any http-address I throw at it.
Yes, I tracert works perfectly well.
I have used ipconfig to clean out the DNS cache, reset the NIC-parameters.
I have emptied the hosts file.
I have reset the IE to original settings, as well as deleted all traces of firefox and chrome and reinstalled those.
I still can not browse the internet using any browser.
Please have some more suggestions ... I will other wise have to use the main part of saturday to re-install windows and the programs ... and one can better use one's time on an sunny, warm and calm autumn day ...

 

[VirtualLarry]

Have you reset you IP stack and Winsock?

Do you have anti-virus or anti-malware installed? Sometimes, they install something that intercepts web requests and does security scanning on them. I would un-install all AV and AM software, and then reset the IP stack and winsock, and then try browsing.

If you can sucessfully nslookup www.google.com, and get an IP, then it sounds like name resolution (port 53, generally UDP) is working. Have you tried browsing to the IP address that you get when you ping www.google.com or nslookup www.google.com ?

What happens with https sites? Same thing?

What is the browser error? Server unreachable?

 

[dave_the_nerd]

Do you have an HTTP proxy configured in your internet settings?

 

[TreyRandom]

If you can ping, then your problem either:
1 - exists in the software you're using to reach sites using port 80 (HTTP),
2 - something's blocking/intercepting port 80 traffic,
3 - or the stack in your OS no longer knows how to interpret port 80 traffic.

The first option should have been fixed by using different browsers or by reinstalling, which you've done.

The second option could be caused by malware or by the configuration of a proxy server. And, as Larry mentioned above, anti-malware solutions sometimes intercept Web requests to scan them for malware. It is possible that the registry cleaner has broken this functionality.

The third option, as you've guessed, could have been caused by the registry cleaner. I know this is like closing the door after the horse has left the barn, but once you get this particular "horse" fixed, I wouldn't recommend that you use registry cleaners in the future. Yes, I know you've used them "for ages", but for ages I've seen things like what you've described after people have used registry cleaners.

 

[petrusbroder]

Well, the interesting thing is, that I can use any browser to surf the LAN, I can reach the router's web interface, my back-up computer's web interface, etc. doesn't that indicate that port 80 is OK?
I do not have/use any proxy.
I have searched for malware and have not found any (which does not mean that there is none ... )
I have no idea about how to remove whatever is blockning port 80, considering that it does not matter if the computer's firewall is on or off, I still can not browse ...
Could a port scanner help? (AFAIK not ..., but I know too little).

The question is: how do I repaire the stack?

And yes, I will avoid registry cleaners. LoL!

 

[biodoc]

Have you checked the router logs to see if there's a clue there?

 

[Orange Kid]

Had a similar problem in the past. The router had multiple addresses for one machine. Had to shut down all the appliances that used the router except one machine and cleared out all the cached ip's manually, shutdown the last machine and rebooted the router. the fired up each appliance one at a time and checked the router as each came on then set names and static ip's for all one at a time. All has worked good since. If you get two ip's for one machine it gets fubar'd and I think it calls back on it's self (does that make sense?)
Then again maybe I just got lucky

 

[rsutoratosu]

i had this issue on a server before, i can hit anything lan but not out of the lan, all the workstation can hit the server no problem.

end up deleting the arp cache..

http://www.techrepublic.com/blog/windows-and-office/quick-tips-flush-the-arp-cache-in-windows-7/

 

[QuietDad]

Check your TCP/IP setting for your network adapter and make sure you have either "get IP address automatically, or if using a static IP on the PC, the Gateway setting is pointing to the router or wherever your DHCP services are being configured

 

[John Connor]

As suggested reset the TCP/IP stack. These are diffrent instructions.

1. Click Start > All Programs > Accessories, right-click on Command Prompt and choose Run as administrator. Windows 8 users press [Windows Key] + [X] and select Command Prompt (Admin).
2. At the command prompt type: netsh winsock reset catalog and press [Enter].
3. Next type: netsh int ip reset reset.log and press [Enter].
4. Restart your PC for the changes to take effect.

http://www.windows-secrets.co.uk/2013/08/repair-the-windows-87vista-tcpip-stack/


If that doesn't work and you have a system restore point try that.

 

[petrusbroder]

Thanks for all the good advice. I really have learned a lot about e.g.netsh etc.

• I have reset the router to factory settings (cleaned out all stuff there) while all computers (incl. iPads, iPods, iPhones, Samsungs, laptops, HTPC, crunchers) were shut down. Then I started the router, added one applience at a time, checked all settings. No applience has more than one IP.
• I have successfully emptied the arp-cache.
• I have successfully emptied other caches.
• I have reset winsock.
• I have reset the TCP/IP-stack several times.
• I have flushed the DNS-cache several times.
• I have reinstalled Firefox, reset IE to factory settings.
• I have -as before- only static IP-addresses for my computers and other devices and all computers have only one IP.
• I have shut down the firewall in the computer, I can not browse...
• I can not disable the firewall in the router but I have temporarily written a rule, which allowed the affected computer to communicate in and out without being blocked. No dice.
• I have scanned the computer for malware with five different scanners - no malware found, no root-kit, nothing...
• I have no proxy.
• I have standard settings for my firewall.
• Firewall on or off does not affect the behavior - I still can not browse.
• If I disable the firewall, I can scan for all the ports in the affected computer from an other computer on the LAN - and port 80 is visible.
• I can ping using an IP and e.g. www.google.com (I have tried several addies)
• I can successfully tracert any http-addy.
• It does not matter if I try to access an http or https-addy, it still does not work.

I have cleaned all the caches in one sitting, restarted the computer at the end. All has been repeated at least three times. No other computer has any problems.
I have not tried to use an other firewall than the one included in Win 7.
Any more ideas?

If not, I'll reinstall the system Sunday ... the day tomorrow promises to be to nice for indoor stuff.

 

[QuietDad]

Before you reinstall Windows, delete the network adapter from Device Manager and reboot the PC. Let windows refind it and set it up all over again. Also try turning off WIndows Firewall or check it to make sure the Firewall is allowing HTTP AND the brower application thru,

 

[VirtualLarry]

I see that you still haven't tried what I suggested. Uninstall your anti-virus and anti-malware programs. Then test connectivity. If it works, try re-installing them.

 

[Fardringle]

Try what VirtualLarry said, then if that doesn't work give Windows Repair AIO a try. I've had it fix quite a few strange problems on various computers I have worked on recently.

 

[Ketchup]

I see that you still haven't tried what I suggested. Uninstall your anti-virus and anti-malware programs. Then test connectivity. If it works, try re-installing them.

I have seen more than one user report a firewall issue like this. Turn it off, even if it's just windows. Trying turning ipv6 off as well.

 

[VirtualLarry]

Trying turning ipv6 off as well.

That's a really good thought. If Windows thinks it has an IPv6 connection to the internet, some browsers will prefer that to IPv4, and if the IPv6 leads no-where, then you don't have connectivity. That might be the issue.

 

[Rudy Toody]

I have seen more than one user report a firewall issue like this. Turn it off, even if it's just windows. Trying turning ipv6 off as well.

That's a golden moment!

According to this whizbang electronic sundial, Peter won't be up for a couple of hours.

 

[Icecold]

[*] I have -as before- only static IP-addresses for my computers and other devices and all computers have only one IP.

I looked through the thread and could not find anywhere where you set it back to DHCP. Have you tried that?

I have had issues where seemingly correct static settings in Windows were not functioning correctly, but upon setting it obtain the IP automatically everything worked fine. Maybe there is a device on your network that's causing an IP conflict and it's causing these flaky issues.

Edit: maybe also post ipconfig /all results from both a machine that is functioning correctly and that machine.

 

[petrusbroder]

Thanks for all the ideas and advice!

• I have uninstalled the AVP and all antimalvare programs.
• I have disabled the firewall
• I have disabled IPv6
• I have again emptied the arp-cache.
• I have again emptied other caches.
• I have again reset winsock.
• I have reset the TCP/IP-stack several times.
• I have flushed the DNS-cache several times.
• I have deleted the NIC from the device manager and reinstalled it with the latest driver.
• I have tried if changing from static IP-addresses to DHCP would make a difference, it did not. Back to static IP-addresses.

I have also checked the router, all is well there; one entry for each computer, etc. The router logs do not show anything of interest - no error messages, etc.
I have used some 10 hours (in two days) to try to solve this problem.

It is not yet solved. I'll not do anything drastic (such as a new install) today. But tomorrow, when I have the whole evening for myself, then the computer will be reborne.

 

[VirtualLarry]

Thanks for all the ideas and advice!

• I have uninstalled the AVP and all antimalvare programs.
• I have disabled the firewall
• I have disabled IPv6
• I have deleted the NIC from the device manager and reinstalled it with the latest driver.
• I have tried if changing from static IP-addresses to DHCP would make a difference, it did not. Back to static IP-addresses.

It is not yet solved. I'll not do anything drastic (such as a new install) today. But tomorrow, when I have the whole evening for myself, then the computer will be reborne.

Hmm, OK, I think I might be out of ideas for you. This one is a toughie, for certain.

 

[Ketchup]

This is quite puzzling.

Have you tried a different port on the router?

Are you using any customized nic settings in either end?

Can others on the network connect to a shared folder on your mschine?