Can't access certain website on cable modem--DNS problem?

[Guest]

The follwing text is from a chat session with Adelphia, my cable ISP. I
tried their suggestions (defrag, etc.), but no help. Can anyone tell me if
the problem is really with my computer and/or windows?

Mary B > Thank you for contacting Adelphia's High Speed Internet Support.
Please describe how I may assist you while I look into your account
information and contact history.
alexlurch > Adelphia appears to have blocked access to the site
www1.prevx.com (213.52.140.88). I can access the site if I use a dialup
connection with another ISP, but not thru my adelphia powerlink cable modem
connection. If I use a proxy server with the powerlink connection, I can also
access it. The site (Prevx) is for an anti-malware intrusion protection
system and I would like to be able to access it. Please let me know why it is
blocked, and if there is not a good reason, I request the blocking be
removed. Thanks!
Mary B > Please try http://www.prevx.com/ and tell me what the redirect does.
alexlurch > I am able to get to www.prevx.com, where as you say there is a
redirect to www1.prevx.com. The redirect fails, and I get a "page cannot be
displayed" error. Again, the redirect works OK if I use a proxy server or
dialup with another ISP.
Mary B > Can i have your HFC Mac ID please?
alexlurch > Not sure what that is? How can I find it?
Mary B > It is on your Modem.
alexlurch > 00E06F94F56A
Mary B > One more moment please.
Mary B > Do you use a router?
alexlurch > No
Mary B > Please click on Tools, Internet options and click on the Privacy
Tab. What is listed there?
alexlurch > Medium. I don't think this setting would be an issue becuase
again, I can access the site thru another ISP on the same computer with the
same Internet settings.
Mary B > Actually, I have verified that this is not an issue with the
Adelphia server. I have checked recursive DNS in your area and the page
resolves perfectly.
alexlurch > Hmm...so what is the issue then?
Mary B > I do not know, that is why I was trying to help you troubleshoot
your browser.
alexlurch > Could it be a hardware issue with the cable modem? The reason I
think it has something to do with the Adelphia connection in some way is that
when I use the same computer to access the page thru SBC Yahoo dialup, it
works fine.
Mary B > I understand that, however it is not an issue with Adelphia. As I
have explained, your DNS server resolves the domain to an IP. If Adelphia was
having an issue, it would say 'Domain not found'.
Mary B > Can you Ping www1.prevx.com ?
Mary B > Do you have a firewall?
alexlurch > Ping doesn't work (request timed out). I have Zone alarm. Same
results if the firewall is disabled.
Mary B > Zone Alarm does not "disable" completely unless it is shut down on
Start Up. Please do that and try it again.
alexlurch > I physically ended the Zone Alarm program (shut it down). By the
way, again, with SBC Yahoo I can access the site even with Zone Alarm running
Mary B > Alright. As I stated, this is not a problem with Adelphia's DNS
server, I have offered to troubleshoot with you and have offered suggestions.
Mary B > Is there anything else I can answer for you tonight?
alexlurch > I'm a little disappointed with your answer. With the same
computer but a different ISP I can access the site yet with Adelphia I can't,
and you say that the problem is not with Adelphia? How can that logically be
true?
alexlurch > How about also the issue of the faulty modem hardware?
Mary B > Are you using XP?
alexlurch > yes
Mary B > It is not your modem, as the configuration file is not
individualized to you, it is the same that all customers get.
alexlurch > OK, could it be something in the network connections settings?
can you walk me thru any steps particular to Adelphia there?
Mary B > With SBC Dialup, your connection is PPP (Point to Point Protocol)
the DNS on PPP is done on the server. You are using DHCP (Dynamic Host Client
Protocol) with Cable. This means DNS is handled on your PC.
alexlurch > OK, what does that mean to me?
Mary B > Your PC is not handling the DNS properly.
alexlurch > What can I do to fix that? Where should I look?
alexlurch > Also, why I can I access the site with adelphia if I use a proxy
server? Wouldn't that be going thru the same PC settings?
Mary B > I just spoke with a network engineer and his suggestion is to clear
your cache and cookies, run a defrag and do generaly maintenance on your PC.
Mary B > Using a Proxy Server holds the cached DNS, this is why it works.
alexlurch > OK, I'll give it a try. Why would this seem to be the only site
that gives me problems? And, if that doesn't do it, what else can I do to
investigate the issue of not handling the DNS?
Mary B > You will want to contact Microsoft with running an SFC scan to
resolve this.
alexlurch > OK
Mary B > Is there anything else I can answer for you tonight?
alexlurch > No
Mary B > Thank you for chatting with Adelphia's High Speed Internet Support.
Please be sure to participate in our chat survey before returning to the
Power Page. We appreciate your feedback. Have a good day.

 

[Haggis]

The follwing text is from a chat session with Adelphia, my cable ISP. I
tried their suggestions (defrag, etc.), but no help. Can anyone tell me
if
the problem is really with my computer and/or windows?

Mary B > Thank you for contacting Adelphia's High Speed Internet Support.
Please describe how I may assist you while I look into your account
information and contact history.
alexlurch > Adelphia appears to have blocked access to the site
www1.prevx.com (213.52.140.88). I can access the site if I use a dialup
connection with another ISP, but not thru my adelphia powerlink cable
modem
connection. If I use a proxy server with the powerlink connection, I can
also
access it. The site (Prevx) is for an anti-malware intrusion protection
system and I would like to be able to access it. Please let me know why it
is
blocked, and if there is not a good reason, I request the blocking be
removed. Thanks!
Mary B > Please try http://www.prevx.com/ and tell me what the redirect
does.
alexlurch > I am able to get to www.prevx.com, where as you say there is a
redirect to www1.prevx.com. The redirect fails, and I get a "page cannot
be
displayed" error. Again, the redirect works OK if I use a proxy server or
dialup with another ISP.
Mary B > Can i have your HFC Mac ID please?
alexlurch > Not sure what that is? How can I find it?
Mary B > It is on your Modem.
alexlurch > 00E06F94F56A
Mary B > One more moment please.
Mary B > Do you use a router?
alexlurch > No
Mary B > Please click on Tools, Internet options and click on the Privacy
Tab. What is listed there?
alexlurch > Medium. I don't think this setting would be an issue becuase
again, I can access the site thru another ISP on the same computer with
the
same Internet settings.
Mary B > Actually, I have verified that this is not an issue with the
Adelphia server. I have checked recursive DNS in your area and the page
resolves perfectly.
alexlurch > Hmm...so what is the issue then?
Mary B > I do not know, that is why I was trying to help you troubleshoot
your browser.
alexlurch > Could it be a hardware issue with the cable modem? The reason
I
think it has something to do with the Adelphia connection in some way is
that
when I use the same computer to access the page thru SBC Yahoo dialup, it
works fine.
Mary B > I understand that, however it is not an issue with Adelphia. As I
have explained, your DNS server resolves the domain to an IP. If Adelphia
was
having an issue, it would say 'Domain not found'.
Mary B > Can you Ping www1.prevx.com ?
Mary B > Do you have a firewall?
alexlurch > Ping doesn't work (request timed out). I have Zone alarm. Same
results if the firewall is disabled.
Mary B > Zone Alarm does not "disable" completely unless it is shut down
on
Start Up. Please do that and try it again.
alexlurch > I physically ended the Zone Alarm program (shut it down). By
the
way, again, with SBC Yahoo I can access the site even with Zone Alarm
running
Mary B > Alright. As I stated, this is not a problem with Adelphia's DNS
server, I have offered to troubleshoot with you and have offered
suggestions.
Mary B > Is there anything else I can answer for you tonight?
alexlurch > I'm a little disappointed with your answer. With the same
computer but a different ISP I can access the site yet with Adelphia I
can't,
and you say that the problem is not with Adelphia? How can that logically
be
true?
alexlurch > How about also the issue of the faulty modem hardware?
Mary B > Are you using XP?
alexlurch > yes
Mary B > It is not your modem, as the configuration file is not
individualized to you, it is the same that all customers get.
alexlurch > OK, could it be something in the network connections settings?
can you walk me thru any steps particular to Adelphia there?
Mary B > With SBC Dialup, your connection is PPP (Point to Point Protocol)
the DNS on PPP is done on the server. You are using DHCP (Dynamic Host
Client
Protocol) with Cable. This means DNS is handled on your PC.
alexlurch > OK, what does that mean to me?
Mary B > Your PC is not handling the DNS properly.
alexlurch > What can I do to fix that? Where should I look?
alexlurch > Also, why I can I access the site with adelphia if I use a
proxy
server? Wouldn't that be going thru the same PC settings?
Mary B > I just spoke with a network engineer and his suggestion is to
clear
your cache and cookies, run a defrag and do generaly maintenance on your
PC.
Mary B > Using a Proxy Server holds the cached DNS, this is why it works.
alexlurch > OK, I'll give it a try. Why would this seem to be the only
site
that gives me problems? And, if that doesn't do it, what else can I do to
investigate the issue of not handling the DNS?
Mary B > You will want to contact Microsoft with running an SFC scan to
resolve this.
alexlurch > OK
Mary B > Is there anything else I can answer for you tonight?
alexlurch > No
Mary B > Thank you for chatting with Adelphia's High Speed Internet
Support.
Please be sure to participate in our chat survey before returning to the
Power Page. We appreciate your feedback. Have a good day.

search your computer for a file called "hosts" , check andsee if the IP for
that site is in the list (you can open it in notepad)

 

[Hans-Georg Michna]

The follwing text is from a chat session with Adelphia, my cable ISP. I
tried their suggestions (defrag, etc.), but no help. Can anyone tell me if
the problem is really with my computer and/or windows?

Alex,

hehe, funny! Those guys and gals have their ways of saying, we
have no clue. -)

Next thing I'd do is a tracert to the problem host, similar to
ping. It should show you the routers along the way.

One possibility is a routing misconfiguration within the
Adelphia network. This could show up in the tracert result by
either the chain breaking off at some point or by the same
router occurring twice (a deadly routing loop).

It is, however, possible that there is a problem on your
computer. You could find that out by using a different computer
on that same cable connection.

One possibility of many is Winsock corruption, possibly in
connection with spyware.

You could work your way through
http://www.michna.com/kb/wxnet.htm and see if it comes up with
something relevant.

Hans-Georg

 

[Guest]

Haggis, I checked the Hosts file, and just to be sure I deleted all entries.
Still the same issue.

Hans-Georg, I was thinking along the same lines as you...I brought home my
Windows 2000 laptop from work. Could access the site just fine at work, but
when I hooked it up to my Cable modem at home, same problem again with this
other PC. I've tried tracert, and the request times out on the third hop.
However, this seems to happen with all web sites, even the ones I have no
problem reaching through a browser--even "adelphia.net".

 

[Hans-Georg Michna]

Hans-Georg, I was thinking along the same lines as you...I brought home my
Windows 2000 laptop from work. Could access the site just fine at work, but
when I hooked it up to my Cable modem at home, same problem again with this
other PC. I've tried tracert, and the request times out on the third hop.
However, this seems to happen with all web sites, even the ones I have no
problem reaching through a browser--even "adelphia.net".

Alex,

this is rather peculiar. My first thought is that you may have
some special software (or hardware) installed that causes this
problem.

Check all of your installed software and look particularly for
software that is related to networking or security. Look for
third party configuration tools, for example. But it would have
to be something that's installed on all of the computers with
which you tested.

It could be some kind of spyware that infected more than one of
your computers.

Something could be wrong with the cable modem as well. I tend to
suspect that now. Could you try to use somebody else's laptop
for a short test?

Hans-Georg