Problem with DNS

[eeeboy]

I am passing my worst dayz because I cant use my internet connection [ I getting this by LAN] . The problem is DNS.

I found my DNS server does not work most of the time. Other LAN users except me are not facing this problem. I can eable to use for a very little time 4-5 minz .....sometimes I have found that If i change my private ip then it works for 5 minz but after that it is dead again.

I guessed this is due to a virus. For this reason I have formatted My system drive and install operating system again but nothing has changed. I have tried two antivirus software 1.Norton Antivirus 2. Avira Anitvirus. I have Zone alarm Pro [latest version ...most proble 6.** something like that]. even I cant find any way how this virus could get in because I have firewall , antivirus , I did not open any unwanted mail , download any malicious / unwanted / un known software.

By the way I have found that I have one entry in My firewall acception list and that is "dnsdn.exe" which is located in C:\Windows\System32

I am not sure whether its really reside here or it's a virus.


Plz help me ..... suggest me what to .do .........Thanx in advance...

[Will.Spencer]

Let's do some troubleshooting!

1. What do you see when you use the `nslookup` command?

Here is what I see when I enter `nslookup` and then do a forward lookup on www.sony.com:

C:\>nslookup
Default Server:  cns.beaverton.or.bverton.comcast.net
Address:  68.87.69.146

> www.sony.com
Server:  cns.beaverton.or.bverton.comcast.net
Address:  68.87.69.146

Non-authoritative answer:
Name:    www.sony.com
Address:  160.33.26.10

>

What do you see when you execute the same commands?


2. What happens when you manually configure your DNS server to 4.2.2.2?

Click <Start>
Click <Control Panel>
Click <Network Connections>
Double-Click the appropriate network connection
Click <Properties>
Scroll down to <Internet Protocol (TCP/IP) and double-click it
Check "Use the following DNS server addresses:"
Enter "4.2.2.2" as your preferred DNS server
Click <OK>
Click <OK> again

Now try to use the Internet. Is DNS now working for you?

[Sneaux]

WHAT I DONT EVEN UNDERSTAND ANY OF THIS!

[eeeboy]

well this is a virus and I m sure about it because I have done this things.

In my pc , I have put a new lan card, try to use but the same thing occurs. Then I have tried by changing my wire, nothing changed but with my this lan card I can use internet form other pc.

Actually I put the logs when I use netstat :

C:\>netstat

Active Connections

  Proto  Local Address          Foreign Address        State
  TCP    powershell:1068        207.46.4.45:1863       ESTABLISHED
  TCP    powershell:1460        80.239.144.76:ftp      ESTABLISHED
  TCP    powershell:1462        207.68.178.61:http     CLOSE_WAIT
  TCP    powershell:1479        66.37.153.81:http      ESTABLISHED
  TCP    powershell:1485        unused.66.37.153.81.firstlink.com:http  ESTABLIS
HED
  TCP    powershell:1492        unused.66.37.153.81.firstlink.com:http  ESTABLIS
HED
  TCP    powershell:1493        unused.66.37.153.81.firstlink.com:http  ESTABLIS
HED
  TCP    powershell:1494        unused.66.37.153.81.firstlink.com:http  ESTABLIS
HED
  TCP    powershell:1495        unused.66.37.153.81.firstlink.com:http  ESTABLIS
HED
  TCP    powershell:1496        unused.66.37.153.81.firstlink.com:http  ESTABLIS
HED
  TCP    powershell:1497        65.54.239.141:http     ESTABLISHED
  TCP    powershell:1498        207.46.5.1:http        ESTABLISHED
  TCP    powershell:1500        kona.kontera.com:http  ESTABLISHED
  TCP    powershell:1501        unused.66.37.153.81.firstlink.com:http  ESTABLISHED

But I am not using any ftp client or logged into any ftp server. Beside this I dont know what is this firstlink.com....

whatever...I just want to mean that not only this time ...many times I see unusal connection to my pc.

Another criteria is that, I have access for little time say 10-15 minz.... after that DNS does not work again.


SO HELP ME.... I can't see any way to make a brand new partition and format of my HDD what is I dont want to do.[/code]

[Will.Spencer]

Originally Posted by eeeboy

I dont know what is this firstlink.com....

FirstLink is the hosting center where The Tech FAQ servers reside. Those connections are you browsing this web site.

That FTP session was to Kapersky Labs, the anti-virus people. Were you downloading Kapersky Anti-Virus?

Please do the two things I recommended earlier in this thread and we will go from there.

[eeeboy]

Ohh..thanx for providing info about firstlink :P and Yes I use kasper Sky.

Now when I am Ok i mean the little time when I can connect to Internet i.e. My dns works properly for me , nslookup works well also and smoothly resolve ip but when I can't access internet i.e. dns is not working properly for me I can't get any ans i mean nslookup not works.

If I put my preferred dns as 4.2.2.2 [and leave secondary/alt , tertiary and so on DNS s blank ], it gives me the following msgs.....

C:\Documents and Settings\Root>nslookup
DNS request timed out.
    timeout was 2 seconds.
*** Can't find server name for address 4.2.2.2: Timed out
*** Default servers are not available
Default Server:  UnKnown
Address:  4.2.2.2

>

Now tell me what to do next ?

[Will.Spencer]

That is very very odd. I can reach the DNS server at 4.2.2.2 with no problems at all.

C:\>nslookup
Default Server:  cns.beaverton.or.bverton.comcast.net
Address:  68.87.69.146

> server 4.2.2.2
Default Server:  vnsc-bak.sys.gtei.net
Address:  4.2.2.2

> www.dell.com
Server:  vnsc-bak.sys.gtei.net
Address:  4.2.2.2

Non-authoritative answer:
Name:    www.dell.com
Addresses:  143.166.83.230, 143.166.224.178

>

Unfortunately, as DNS resolution runs over UDP, DNS problems can be very difficult to troubleshoot.

Reading the thread again, I see that I missed your reference to "dnsdn.exe." I do not find a copy of that on my system. Have you tried renaming the file and rebooting?

I find no reference to that file in Google.

Did you perhaps in the past try to setup Dynamic DNS (DDNS) on that system?