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blocking port 80 on Thinkapd - software problem

Posted: Sun Dec 10, 2006 3:23 pm
by ceron
Hello!

Since i'm new, Welcome people!

I'm having software problem with my Thinkpad(R51e). Every day(but not allways)some program
is blocking port 80, so any outgoing requests to, say http://forum.thinkpads.com ,will
result in error: "cannot display page", "time out" etc. I've made investigation and found
following results:

-routing is ok(i can ping with IP)
-dns is ok(can ping using hostname)
-i'm not using proxy server
-windows xp firewall is disabled
-antivirus software is ok(this happpens with or without antivirus running)
-other services are working ok(p2p,ftp,ssh,pop3)
-logout and login doesn't solve problem
-after reboot everything is ok...for some time

I use tcpview to display state of connection, and when the problem begins
i see 'SYN_SENT', so browser initialize connection, but something is blocking it.
I think, that this is fault of IBM/Lenovo software, because, when the xp was clean,
right after instalation(without any IBM's software, except Power management) everything
was ok.
The funny thing is, that i can grab web page from inside of my LAN(priv. class A network),
everything else hangs at 'SYN_SENT'...

Anyone have idea, what it could be? any suggestions will be helpful.

regards
Chris

Posted: Sun Dec 10, 2006 4:15 pm
by jdhurst
IBM / Lenovo software doesn't prevent browsing (at least, it never has for me).

It is possible to be able to ping without traffic flowing. Assuming DNS to be ok as you say, perhaps MTU size or some other like variable is set improperly.

It may be that you are not using a Proxy Server, but if the Automatic Connection Setting in Internet Tools -> Connections -> Lan Settings may be checked (should not be).

You may have attracted some spyware (Run AdAware) or a virus that your AntiVirus didn't detect (do a full scan to be sure).
... JD Hurst

Posted: Sun Dec 10, 2006 5:04 pm
by tomh009
You should confirm that it's a networking issue rather than a browser problem. Use a command prompt and try something like this:

telnet www.thinkpads.com 80

and see whether you get a connection. If you do, you can confirm that requests work by typing

GET http://www.thinkpads.com/ HTTP/1.0 <ENTER><ENTER>

If you get a bunch of HTML displayed, your networking connection is just fine and you should look into browser problems or possibly some kind of malware.

Posted: Mon Dec 11, 2006 8:44 am
by ceron
jdhurst wrote:IBM / Lenovo software doesn't prevent browsing (at least, it never has for me).

It is possible to be able to ping without traffic flowing. Assuming DNS to be ok as you say, perhaps MTU size or some other like variable is set improperly.
well, the MTU is 1472 on win xp, on linux it's 1500 bytes, however
i remember, that i was reading about problem with ibm(but not lenovo)
software and port 80 on the ibm's site couple of months ago, now i don't know where it was :(
i better start searching ibm's site...
It may be that you are not using a Proxy Server, but if the Automatic Connection Setting in Internet Tools -> Connections -> Lan Settings may be checked (should not be).
it is not checked
You may have attracted some spyware (Run AdAware) or a virus that your AntiVirus didn't detect (do a full scan to be sure).
... JD Hurst
didn't found any spyware

regards
Chris

Posted: Mon Dec 11, 2006 8:48 am
by ceron
tomh009 wrote:You should confirm that it's a networking issue rather than a browser problem. Use a command prompt and try something like this:

telnet www.thinkpads.com 80

and see whether you get a connection. If you do, you can confirm that requests work by typing

GET http://www.thinkpads.com/ HTTP/1.0 <ENTER><ENTER>

If you get a bunch of HTML displayed, your networking connection is just fine and you should look into browser problems or possibly some kind of malware.
yes, i tried this, but since the connection is not established, i cannot issue GET request, it stops at: 'connecting...'

regards
Chris

Posted: Mon Dec 11, 2006 9:33 am
by GomJabbar
Since your problem only happens sometimes, I tend to suspect your software firewall. I have had similar problems with ZoneAlarm. Kerio has not caused any of these problems for me. Try turning off your software firewall and see if your connection comes back.

If this doesn't solve your problem, I framed a search on IBM for port 80. Lotus software is mentioned in some of the hits. Click on the link below and see if anything fits.

Search: +"Port 80" +thinkpad

Posted: Mon Dec 11, 2006 12:38 pm
by DAH
May I respectfully suggest that you try installing this, http://www.microsoft.com/windowsxp/usin ... stics.mspx and following the instruction on that page. Are you running the Symantec Client Security? This program maybe blocking you.

Posted: Mon Dec 11, 2006 3:28 pm
by ceron
DAH wrote:May I respectfully suggest that you try installing this, http://www.microsoft.com/windowsxp/usin ... stics.mspx and following the instruction on that page. Are you running the Symantec Client Security? This program maybe blocking you.
ok, installed this, now i need to wait until problem occurs again...
will post the results...

i'm not using Symantec Client Security and ZoneAlarm, the only
firewall i have is windows xp firewall, which is disabled all the time...

regards
Chris

Posted: Mon Dec 11, 2006 5:29 pm
by jdhurst
ceron wrote:<snip>
1. well, the MTU is 1472 on win xp, on linux it's 1500 bytes, however I remember, that i was reading about problem with ibm(but not lenovo) software and port 80 on the ibm's site couple of months ago, now i don't know where it was :( I better start searching ibm's site...
<snip>
2. Automatic connection is not checked
<snip?
3. didn't found any spyware

regards
Chris
1. Should work. Tweakmaster tells me my connection is Windows default and right now on Wireless, that is 1420. So your value should work. You can try a smaller value if you wish.

2. Good.

3. Good.

You can try repairing the TCP/IP stack, but that doesn't always work.
... JD Hurst

Posted: Wed Dec 13, 2006 2:19 pm
by ceron
today problem occurred again, so i started Network Diagnostics Tool, and the results
are exactly the same as before, plus new one : http, https and ftp are not working.
I'll try repairing tcp/ip stack.

regards
Chris

Posted: Fri Dec 22, 2006 2:32 pm
by ceron
looks like reseting tcp/ip stack solved my problem. week passed after this operation
and everything looks good....back to normal computing :)

thanks everyone for your help

regards
Chris