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The problem is that many programs (such as all IE and other browers) cannot access the network. But let me explain before you get the wrong idea.

I am quite familiar with networking in general, so I can tell you that the outgoing network traffic is not even reaching the network hardware interface. In looking into the problem, I am using Wireshark to monitor network traffic. What happens is that some programs can send packets out (and thus receive responses) but others cannot. For example, anti-virus programs cannot update themselves, but PUTTY can reach anything I send it to.

Tech Support Guy System Info Utility version OS Version: Microsoft Windows XP Home Edition, Service Pack 3, 32 bit Processor: Intel(R) Core(TM)2 Duo CPU E4500 @ 2.20GHz, x86 Family 6 Model 15 Stepping 13 Processor Count: 2 RAM: 1023 Mb Graphics Card: NVIDIA GeForce 7300 LE, 512 Mb Hard Drives: C: Total - 476929 MB, Free - 437737 MB; Motherboard: ECS, GF7050VT-M, 1.0, 00000000 Antivirus: avast! Antivirus, Updated: No, On-Demand Scanner: Enabled

Originally I had McAfee Internet Security installed. Suddenly one day, McAfee was unable to update itself, and IE (and other browsers) stopped working.

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Suddenly one day, you remembered that you had installed X just before the problems started. Solve for X. – boot13 Sep 2 '10 at 5:36
No, boot13. "Originally I had McAfee Internet Security installed" McAfee was installed for a year before this happened. No other X was installed just before this happened. – Beel Sep 2 '10 at 9:29
up vote 0 down vote accepted

Are you saying that no applications other than putty access the network? I find that strange. Maybe it is just a simple DNS issue? Have you tried doing a ping on like and the equivalent of its IP? or ?

See if you can ping both a domain and an IP address. I am suspecting from the lack of info provided that it is either one of these:

  • Firewall (left-over McAfee?)
  • DNS issue (only allows IP access, no dns queries work = no internet for IE/rest).

Check that out, and give us some updates.

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ping has no problem. I think it is a TCP level problem, not an IP problem. Also DNS has no problem - Wireshark shows the DNS succeeding but after that no traffic. I like your suggestion about possible leftover McAfee, as I still see traces of McAfee on the system despite having uninstalled it. I will look for a way to more completely remove McAfee - more complete than its uninstall. – Beel Sep 2 '10 at 6:00
OK, the problem is solved. Jakub, your comment did put me on the right track. The solution was to use MCPR.exe to completely uninstall McAfee. (I also uninstalled Avast.) – Beel Sep 2 '10 at 9:39

Try checking the Windows Firewall and see if it is on strict or if any weird settings have been configured - I would personally go to the last tab and choose the reset option.

Alternatively from the command prompt, you can type:


If you are not using the Windows Firewall, then check the settings on whatever firewall you are using.

If still having the problem, I would check your router and make sure that all outgoing traffic is allowed.

Lastly, if it still has not been resolved, can you provide more information - how you connect to the internet, is this a standard home machine or at an office etc.

share|improve this answer
Thanks for the answer, Wil, but it is not the router: the traffic never even reaches the interface in the machine. Verified that by using WireShark and also TCPview. During testing I turn Windows Firewall off completely, but I did check the settings and reset it using the netsh command you gave. But one detail I need to add to the initial posting is that I installed Avast so I could have some kind of anti-virus. It blocks the web browsers unless I turn off its web scanner. I will uninstall it to see what happens. – Beel Sep 2 '10 at 5:56

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