Strange DNS problem

  • Thread starter Thread starter Tom B
  • Start date Start date
T

Tom B

I have a winXP home version with a very strange problem.
When I use Internet Explorer, I cannot connect to any web
sites by name (eg. yahoo.com) but I can connect using the
IP address for the site (eg. 216.109.112.135). This
indicates a DNS problem.

I ran IPCONFIG /ALL to get the IP address of the DNS
servers. I can ping both DNS servers IP address. But when
I ping by name it reports "ping request could not find
host yahoo.com". I tried adding "216.109.112.135
yahoo.com" to the hosts file but ping still reports could
not find host.

Also when I ran NETSTAT -a the local address column shows
blanks instead of the computer name and port. But
NETSTAT -an does show the IP address and port number.

Something with DNS is really broken on this PC but I'm
not sure how to fix it. Any ideas? Don't really want to
wipe the disk and re-install the OS. Thank in advance for
your help.
 
I have a winXP home version with a very strange problem.
When I use Internet Explorer, I cannot connect to any web
sites by name (eg. yahoo.com) but I can connect using the
IP address for the site (eg. 216.109.112.135). This
indicates a DNS problem.

I ran IPCONFIG /ALL to get the IP address of the DNS
servers. I can ping both DNS servers IP address. But when
I ping by name it reports "ping request could not find
host yahoo.com". I tried adding "216.109.112.135
yahoo.com" to the hosts file but ping still reports could
not find host.

Also when I ran NETSTAT -a the local address column shows
blanks instead of the computer name and port. But
NETSTAT -an does show the IP address and port number.

Something with DNS is really broken on this PC but I'm
not sure how to fix it. Any ideas? Don't really want to
wipe the disk and re-install the OS. Thank in advance for
your help.
Click to expand...

Tom,

What Node Type shows in IPConfig?

Search your entire system drive, including hidden and system folders, for file
"hosts". There is one legit copy, in C:\WINDOWS\system32\drivers\etc\. The
others are possibly bogus, and part (but just part) of the problem. Examine the
contents of each copy found, using Notepad. (HINT: Scroll to the end of each
Hosts file, by hitting Ctrl-End, then back up to the top, page by page, before
deciding that the file is empty. Look out for blank lines at the beginning and
end of the file, after localhost, placed there by an exploit!)

A hosts / lmhosts entry with your ip address, and no name, would make your
computer name show as blanks in "netstat -a". Typically, local names (on your
LAN) are resolved by DHCP / NetBIOS / WINS (or lmhosts). Internet host names
are resolved by DNS (or hosts), or you might have a dns cache on your computer.

<http://support.microsoft.com/default.aspx?scid=kb;en-us;160177>

Cheers,
Chuck
Paranoia comes from experience - and is not necessarily a bad thing.
 
This problem is on a friend's PC. I took my laptop to my
friend's home and removed his PC and connected my laptop
to his DSL line. I made sure my all my TCP/IP properties
were set the same as my friend's PC. With my laptop
connected I could get to all web sites by name and ping
both IP addresses AND DNS names. Therefore I'm sure the
ISPs DNS servers are working correctly.

The node type on both my laptop and his PC
shows "Unknown". I checked his hosts file in
C:\WINDOWS\system32\drivers\etc\ and is has the original
127.0.0.1 localhost AND on the line below I added the
following:

216.109.112.135 yahoo.com

The only other hosts file is in the i386 folder. When I
ping yahoo.com it reports "ping request could not find
host yahoo.com" so it looks like DNS is not functioning
on this PC.

I thought this might be an spyware problem so I installed
Adaware on his PC and it found a lot of stuff which I had
it fix but it did not fix the DNS problem. Is it possible
that some how DNS has been turned-off or disabled on this
PC? Also how can I be sure the DNS cache is working? I
did IPCONFIG /flushdns and got "Successfully flushed the
DNS Resolver Cache" but it did not fix the problem.

Thanks for your help.
-----Original Message-----
Tom,

What Node Type shows in IPConfig?

Search your entire system drive, including hidden and system folders, for file
"hosts". There is one legit copy, in C:\WINDOWS\system32 \drivers\etc\. The
others are possibly bogus, and part (but just part) of the problem. Examine the
contents of each copy found, using Notepad. (HINT: Scroll to the end of each
Hosts file, by hitting Ctrl-End, then back up to the top, page by page, before
deciding that the file is empty. Look out for blank lines at the beginning and
end of the file, after localhost, placed there by an exploit!)

A hosts / lmhosts entry with your ip address, and no name, would make your
computer name show as blanks in "netstat -a".
Click to expand...
Typically, local names (on your
Click to expand...
 
This problem is on a friend's PC. I took my laptop to my
friend's home and removed his PC and connected my laptop
to his DSL line. I made sure my all my TCP/IP properties
were set the same as my friend's PC. With my laptop
connected I could get to all web sites by name and ping
both IP addresses AND DNS names. Therefore I'm sure the
ISPs DNS servers are working correctly.

The node type on both my laptop and his PC
shows "Unknown". I checked his hosts file in
C:\WINDOWS\system32\drivers\etc\ and is has the original
127.0.0.1 localhost AND on the line below I added the
following:

216.109.112.135 yahoo.com

The only other hosts file is in the i386 folder. When I
ping yahoo.com it reports "ping request could not find
host yahoo.com" so it looks like DNS is not functioning
on this PC.

I thought this might be an spyware problem so I installed
Adaware on his PC and it found a lot of stuff which I had
it fix but it did not fix the DNS problem. Is it possible
that some how DNS has been turned-off or disabled on this
PC? Also how can I be sure the DNS cache is working? I
did IPCONFIG /flushdns and got "Successfully flushed the
DNS Resolver Cache" but it did not fix the problem.
Click to expand...

Tom,

Node Type: Unknown is the same as my WinXP systems show.
<http://support.microsoft.com/default.aspx?scid=kb;en-us;160177>

DNS is affected by the LSP subsystem.
<http://support.microsoft.com/?kbid=811259>

Give LSP-Fix and WinsockLSPFix a shot <http://www.cexx.org/lspfix.htm>

Cheers,
Chuck
Paranoia comes from experience - and is not necessarily a bad thing.
 
I did the steps in KB 811259 and everything works great
now! Yeah!!! You're the BEST Chuck! Thanks very much
for your help!!!!!!!!!
-----Original Message-----
Click to expand...
 
I did the steps in KB 811259 and everything works great
now! Yeah!!! You're the BEST Chuck! Thanks very much
for your help!!!!!!!!!
Click to expand...

Excellent! Thanks for the feedback, Tom.

Cheers,
Chuck
Paranoia comes from experience - and is not necessarily a bad thing.
 
I am still stuck -- I have a similar but somewhat different DNS issue. Cannot
connect to the internet on one of the three PC's. Error message when trying
to "Repair" network connection = "Purging the DNS resolver cache". I have
three PC's running XP on a wireless network using a D-Link DI-741P+ router.
The PC attached directly to the router is fine; a laptop is also fine; the
problem PC displays a strong signal from the wireless network but will not
connect to the internet via MS Explorer. It appears to be some kind of
network setting issue? The router is working fine. Any suggestions would be
most appreciated. Thanks.
 
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