In WinXP SP3 "Network Connections", I right click "Repair" the wired "Local Area Connection" but always get an error. How do I clear the DNS cache?
Here is the error I always get (even after rebooting):
Repair Local Area Connection Windows could not finish repairing the problem because the following action cannot be completed: Clearing the DNS cache For assistance, contact the person who manages your network.
Unfortunately, I am the person who "manages" the home network.
How do I repair an Internet connection that won't release the dns cache? (I have a similar problem with the wireless connection which it won't release)
I did try "flushing" the dns cache but it gave a different error:
Microsoft Windows XP [Version 5.1.2600] (C) Copyright 1985-2001 Microsoft Corp. C:\Documents and Settings\kathleen>ipconfig /flushdns Windows IP Configuration Could not flush the DNS Resolver Cache: Function failed during execution.
I don't know what else to check to see what is locking the DNS cache. What could be preventing the DNS cache from flushing?
I found the problem was the "DNS Client" service wasn't running.
I hadn't been running the DNS Client service ever since I set the DNS CLient to "Manual" as per a web site months, or maybe even years ago, which said to disable all unnecessary and unneeded Windows XP services.
Since the Internet connection has been working all that time (the router automatically assigns the DNS to the computer in the home network), I wonder what usful thing the DNS Client does???
What does the DNS Client actually do (besides preventing a network repair)?
I just remembered WHY I set the DNS Client service to Manual. I have a huge hosts file (with spam blocking). I don't remember the problem but that is why I disabled the DNS Client service.
So my question has morphed to ...
What does the DNS Client service actually do (besides slowing down huge hosts files and prevening network repairs)?
For my type of home network, the DNS Client service doesn't appear to do anything useful! :(
I have a giant hosts file which I update daily as I run into web sites I feel act suspiciously (malware, javaware, flashware, annoying popups, etc.). I also remove duplicate entries programatically (unixutils "sort
-u").
In my home network, all the Windows XP SP3 DNS Client seems to (really) do is just two bad things:
- The DNS Client prevent network repairs (by preventing DNS flushes)
- The DNS Client foul ups systems with large hosts files
Apparently the DNS Client service optimizes the performance of DNS name resolution by storing previously resolved names in memory. If the DNS Client service is turned off, the computer can still resolve DNS names by using the upstream DNS servers.
One caveat: On recent Windows versions, the "DNS Client" service is also used to register the computer's network connection in DNS (sends a dynamic update creating a host record on the local DNS server).
formatting link
BTW, I did find out how to start and stop the DNS CLient manually:
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\> net stop dnscache c:\> sc servername stop dnscache
Every time I see an ad displayed in my browser, I find the link and ad it to my hosts file loopback so that I never again see an ad from that site.
It seems the DNS Cache (when enabled), holds these spyware and adware sites in memory somewhere...
C:\Documents and Settings\kathleen>ipconfig /displaydns Microsoft Windows XP [Version 5.1.2600] (C) Copyright 1985-2001 Microsoft Corp. Windows IP Configuration
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---------------------------------------- Record Name . . . . . :
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Record Type . . . . . : 1 Time To Live . . . . : 595859 Data Length . . . . . : 4 Section . . . . . . . : Answer A (Host) Record . . . : 127.0.0.1
yieldmanager.net ---------------------------------------- Record Name . . . . . : yieldmanager.net Record Type . . . . . : 1 Time To Live . . . . : 595859 Data Length . . . . . : 4 Section . . . . . . . : Answer A (Host) Record . . . : 127.0.0.1
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---------------------------------------- Record Name . . . . . :
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Record Type . . . . . : 1 Time To Live . . . . : 595859 Data Length . . . . . : 4 Section . . . . . . . : Answer A (Host) Record . . . : 127.0.0.1
If you're running Firefox, (isn't everyone? ), then just add AdBlock Plus and stop messing around with your Hosts file. I can't even fathom the amount of trouble you're enduring with your method of blocking ads.
Why not research your problem before posting, instead of posting revised messages every ten minutes?
I just remembered WHY I set the DNS Client service to Manual. I have a huge hosts file (with spam blocking). I don't remember the problem but that is why I disabled the DNS Client service. So my question has morphed to ... What does the DNS Client service actually do (besides slowing down huge hosts files and prevening network repairs)?
Actually, the DNS Client speeds up things when one has huge hosts files. Without the DNS Client service, the hosts file is read and processed by every individual application process for every individual query. With the DNS Client service, the hosts file is read and processed once, by the DNS Client service at startup, and then re-read whenever the DNS Client service sees that it has changed.
Every time I see an ad displayed in my browser, I find the link and ad it to my hosts file loopback so that I never again see an ad from that site.
M. Jackson is right that this is a troublesome method of advertisement blocking. DNS is not the solution to WWW browsing problems. HTTP is. Use an advertisment-blocking HTTP proxy server; use a PAC script, or use one of the many WWW browser plug-ins that do what you want to do.
Every once in a while (maybe once a week or once every few weeks or so), the wireless Internet connection goes "down" on the PC.
When I "repair" it, it comes back "up".
I don't really know more than that ... but I've found now that setting the DNS Client to "manual" is what caused the wireless connection to not be able to be repaired. It repairs now that I've started the DNS Client manually.
I wonder whether most people follow the recommendation to disable unnecessary services such as the "DNS Client"?
The subscriptions are just lists of known malware sites, totally free to subscribe (optional too). I just use a hosts file and dont bother with subscriptions.
You can open a browser, and in it type one of those IP address and the web page will open just like you typed it respective URL, either google.com or facebook.com
When the internet was developed (ARPNET at that time), it was deemed that a human would not be able to remember IP addresses of hosts they needed to contact. A mechanism was put in place that gives IP adresses English hostnames.
It's a lot easier to remember facebook.com than 69.63.181.11
So, they devised a scheme to store URL-to-IP mappings. When you type in facebook.com and hit enter, the DNS client, you're PC, see's that a domain name was entered in the address bar and not an IP address.
Since the internet works on IP addresses, and not URLs, your PC contacts the DNS server (usually inside your ISP) and tells it you are looking for facebook.com.
The DNS server then replies to your PC what the IP address of facebook.com is.
The browser then plugs in the IP address instead of the easily memorable URL and off it goes trying to open the web page.
By convention, yes there's usually a space between the command and any switches, but it works equally well, at least in this case, without the space. (It looks strange without a space to me, too.)
Just for the record, I had tried the following commands in WinXP SP3; but both failed due to the fact that the listing and flushing of the DNS cache cannot be accomplished without the "DNS Client" service running.
C:\> ipconfig /displaydns C:\> ipconfig /flushdns
This is what I previously reported for those commands (before enabling the otherwise unnecessary DNS Client service).
Microsoft Windows XP [Version 5.1.2600] (C) Copyright 1985-2001 Microsoft Corp. C:\Documents and Settings\kathleen>ipconfig /flushdns Windows IP Configuration Could not flush the DNS Resolver Cache: Function failed during execution.
C:\Documents and Settings\kathleen>ipconfig /displaydns Microsoft Windows XP [Version 5.1.2600] (C) Copyright 1985-2001 Microsoft Corp. Windows IP Configuration
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---------------------------------------- Record Name . . . . . :
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Record Type . . . . . : 1 Time To Live . . . . : 595859 Data Length . . . . . : 4 Section . . . . . . . : Answer A (Host) Record . . . : 127.0.0.1
yieldmanager.net ---------------------------------------- Record Name . . . . . : yieldmanager.net Record Type . . . . . : 1 Time To Live . . . . : 595859 Data Length . . . . . : 4 Section . . . . . . . : Answer A (Host) Record . . . : 127.0.0.1
formatting link
---------------------------------------- Record Name . . . . . :
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Record Type . . . . . : 1 Time To Live . . . . : 595859 Data Length . . . . . : 4 Section . . . . . . . : Answer A (Host) Record . . . : 127.0.0.1
BTW, I also found out how to start and stop the DNS caching: c:\> net stop dnscache c:\> sc servername stop dnscache
Services - Disabling Negative Myth - "Disabling certain Services improves performance." Reality - "Disabling certain Services actually reduces performance." Automatic DNS Client Service - "The overall performance of the client computer decreases and the network traffic for DNS queries increases if the DNS resolver cache is deactivated. This effectively reduces Internet Performance for sites you have previously visited and puts an unnecessary load on your ISP's DNS server."
Large Hosts Files "Large Hosts Files cause Internet related slowdowns due to DNS Client Server Caching. This negatively effects your browsing speed. AntiSpyware Hosts File authors irresponsibly recommend disabling the DNS Client Service to solve this problem. This is not a solution. The overall performance of the client computer decreases and the network traffic for DNS queries increases if the DNS resolver cache is deactivated. This effectively reduces Internet Performance for sites you have previously visited and puts an unnecessary load on your ISP's DNS server." Notes - There is a much better solution for bad site blocking using SpywareBlaster which more intelligently use's Internet Explorer's built-in Zone Security settings and the registry. Mozilla/Firefox protection is also provided.
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