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On my Windows XP workstation, I can find the machine I want to connect to in DNS with nslookup:

nslookup wolfman
Server: dns.company.com
Address: 192.168.1.38

Name: wolfman.company.com
Address: 192.168.1.178

But, when I try to connect to that machine, I get an error telling me that the machine can't be found (i.e., can't be looked up in DNS):

C:\> ping wolfman
Ping request could not find host wolfman. Please check the name and try again.

I am able to connect if I use the IP address directly:

C:\> ping 192.168.1.178

Pinging 192.168.1.178 with 32 bytes of data:

Reply from 192.168.1.178: bytes=32 time=41ms TTL=126
Reply from 192.168.1.178: bytes=32 time=41ms TTL=126
Reply from 192.168.1.178: bytes=32 time=44ms TTL=126
Reply from 192.168.1.178: bytes=32 time=38ms TTL=126

I could work around this by adding an entry to my hosts file, but I would rather find out why this is happening. The problem is transient, most of the day I can connect to the machine just fine.

How is this possible?

ETA: I left this out for brevity, but it was asked for:

C:\> ping wolfman.company.com
Ping request could not find host wolfman.company.com. Please check the name and try again.

ETA: Other applications get the same results. I only tried ping to simplify. telnet can't connect, Cygwin apps print a "unknown host wolfman" message.

Update: Using wireshark, I found that my workstation is not attempting a DNS lookup. It's just reporting the "could not find host" error message.

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2  
What happens if you ping wolfman.company.com? –  SLaks Oct 29 '12 at 19:14
1  
Do you have wireshark installed? You could see if ping uses something else when trying to resolve the host. Have you tried telnet and ftp too? –  ott-- Oct 29 '12 at 19:51
    
You could add a default DNS suffix for .company.com. –  billc.cn Oct 29 '12 at 20:25
    
@billc.cn I already have that DNS suffix. –  skiphoppy Oct 30 '12 at 16:35
1  
Possible duplicate of: superuser.com/questions/220471/… –  Oliver Salzburg Nov 19 '12 at 17:57

11 Answers 11

I believe that nslookup opens a winsock connection on the DNS port and issues a query, whereas ping uses the DNS Client service. You could try and stop this service and see whether this makes a difference.

Some commands that will reinitialize various network states :

Reset WINSOCK entries to installation defaults : netsh winsock reset catalog
Reset TCP/IP stack to installation defaults : netsh int ip reset reset.log
Flush DNS resolver cache : ipconfig /flushdns
Flush routing table : route /f (reboot required)

Some sites also recommend uninstalling and reinstalling SP3 in this case.

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I would bet Active Directory is probably active, but I do not know how to test. –  skiphoppy Nov 20 '12 at 14:51
1  
I disabled the DNS Client service, and the problem appeared to go away! Not sure yet if it was a fluke. The problem didn't come back when I restarted the service. –  skiphoppy Nov 20 '12 at 14:55
2  
Sometimes just stopping and restarting the service fixes DNS problems (don't ask me why). The question is how long this will last. Some unlucky people need to repeat it again and again. –  harrymc Nov 20 '12 at 16:06
    
Yes, if that's the case, I want to know why! I am going to try this the next time the problem occurs. If it appears to fix it then, I'm going to drag in IT admins from the main corporate office and get them to tell me why. :) And you'll get the bounty if that appears to be the fix. –  skiphoppy Nov 20 '12 at 16:36
    
sfc /scannow in case the dns client service system files are corrupt subtly? I've also seen some people with similar problems caused by a virus. –  Jon Kloske Nov 26 '12 at 5:27

nslookup works different to other commands when resolving names/ip addresses on Windows.

The normal resolution method on Windows is as follows:

  1. The client checks to see if the name queried is its own.
  2. The client then searches a local Hosts file, a list of IP address and names stored on the local computer.
  3. Domain Name System (DNS) servers are queried.
  4. If the name is still not resolved, NetBIOS name resolution sequence is used as a backup. This order can be changed by configuring the NetBIOS node type of the client.

nslookup on the other hand is used for testing Domain Name Servers.

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Are there any settings that can move the NetBIOS query higher up in that list? I have the gut feeling that the NetBIOS lookup is involved somehow, but since the DNS query is definitely working I can't see how it would ever get to that step, if the sequence above is immutable. –  skiphoppy Nov 20 '12 at 14:49

Try ipconfig /displaydns and look for wolfman. If it's cached as "name does not exist" (possibly because of a previous intermittent failed lookup), you can flush the cache with ipconfig /flushdns.

nslookup doesn't use the cache, but rather queries the DNS server directly.

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I tried: it's not cached. And clearing the cache doesn't fix the issue, either. –  skiphoppy Nov 20 '12 at 14:46
    
Can you post the output of nslookup -all? Is novc listed? –  craig65535 Nov 20 '12 at 18:22

Maybe wolfman.company.com is listed in C:\Windows\system32\drivers\etc\hosts ?

nslookup bypasses that file and always asks DNS, while ping and other tools first of all look up in "hosts" file, then in DNS.

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Good thought! But I checked, and neither of the machines I've seen this issue with are listed in hosts. –  skiphoppy Nov 20 '12 at 14:47

Is this only happening on this one computer? Can you visit websites through your web browser? Is this machine by any chance an Acer?

Is this a brand new install on a machine? Was it recently updated? What Service Pack of XP are you running?

I have had this happen before and re-installing SP3 fixed it.

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ping uses the ICMP protocol, specifically the 'Echo Request' and 'Echo Reply'.

many networks disable ICMP utilities in order to prevent attacks or basic network scanning. I've found many routers you purchase come with a setting to disable ping and like utilities enabled by default.

you can find more about ICMP here:

http://en.wikipedia.org/wiki/Internet_Control_Message_Protocol

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5  
Yes, but before using ICMP, the domain has to be resolved to an IP address as usual. So this is not the issue here. –  Michael Nov 23 '12 at 2:25

Adding an entry in the file c:/windows/system32/drivers/etc/hosts might fix it.

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i have encountered this when we migrated to windows 7 from windows XP, the issue was related to a Windows 7 Multi Label DNS Query issue.

Allow DNS Suffix Appending to Unqualified Multi-Label Name Queries - see:

http://computerstepbystep.com/allow_dns_suffix_appending_to_unqualified_multi_label_name_queries.html

Hope this helps

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1  
Welcome to Super User! Whilst this may theoretically answer the question, it would be preferable to include the essential parts of the answer here, and provide the link for reference. –  Canadian Luke Mar 21 at 17:40

Try ping with hostname followed by a dot. So instead of ping wolfman use ping wolfman.

That should get you resolving without having to do workarounds with hosts file, etc.

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If on mac os x it might be an DNS Cache problem:

Dump the cache

sudo killall -HUP mDNSResponder
sudo dscacheutil -flushcache
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I've struggled with a similar issue and have tried the solution suggested by @harrymc. I found what eventually seems to (at least somewhat) work at the microsoft technet forum (nslookup works but nothing else has DNS on standalone Win7 PC)

Here's the quote:

... try to use the command below to flush and reset a client resolver cache for test.

ipconfig /flushdns

ipconfig /registerdns

Please refer to the link below for more details. http://jefferyland.wordpress.com/2011/07/28/quick-review-of-flushdns-registerdns-and-dns-queries/

So basically what was missing for me was ipconfig /registerdns

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