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What is QuickDNS for? Running
Overview Output
DNS Lookup vs Hosts. Caveats
Advantages of QuickDNS Windows 10
Disadvantages of QuickDNS Acquiring QuickDNS
Format of Hosts. File Links

What is QuickDNS for?

  1. It speeds up your browser when it looks up a website.
  2. It enables your browser to find critical websites even when your DNS (Domain Name Service) servers are down.


How does it work? Let me explain with a familiar analogy. When you telephone someone, you either:

When your browser goes to a website, e.g., similarly, it needs to look up the number to get the IP Your computer does this automatically every time you visit a website by first visiting a computer on the web called a DNS server to look up the name for you.

DNS Lookup vs Hosts. Lookup

There are two problems with this:
  1. it adds an extra second or more to fetching a web page. It is a bit like looking up the number in an electronic phone book every time you make a phone call.
  2. if there is anything wrong with the DNS server, you are dead in the water, even if the website you want to visit is fully functional.

What you can do is create a little electronic address book of commonly visited websites called C:\Windows\system32\drivers\etc\hosts. The computer does not have to pester the DNS server to get these numbers. You can create this file manually with a text editor such as Notepad. You can manually look up the IPs of your common servers with the ping utility, e.g. on the command line type:


The problem is, from time to time, the IPs change and your browser gets sent to the wrong IP. You need something to keep the list of IPs up to date. That is where QuickDNS comes in. You might run it every week or every time you reboot or every time lookup seems to be failing.

Advantages of QuickDNS

The advantages of using QuickDNS are:

Disadvantages of QuickDNS

Format of Hosts. File

Here is what a typical C:\Windows\System32\drivers\etc\hosts. file looks like. Most of the comments were put there by Microsoft. The lines with an IP and domain, I put there with a text editor. # introduces a comment. # leave marks a line that QuickDNS should leave alone.

You can disable a website with a line like this:

QuickDNS does not support the older W95, W98, Me, NT and W2K.


You can run QuickDNS with this little bat file:
rem running QuickDNS
rem adjust drive and directory to match where you put the quickdns.jar file.
cd \com\mindprod\quickdns
java -jar quickdns.jar

and it will check all the IPs and update any that have changed. It will leave alone those marked with #leave. Even when it does not change any IPs, it still tidies up the hosts. file into neat columns. It never changes the order of the entries or removes comments.

If you want to run this bat file automatically, every time you boot, put a shortcut to it in: C:\Users\user\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup\ or use Ace utilities to insert a registry entry to arrange to have it run on boot.

Surprisingly, Windows immediately notices the changes and puts them into effect right away. You don’t have to reboot.


Typical output will look like this:

QuickDNS updated: to for
QuickDNS updated: to for
QuickDNS updated: to for
QuickDNS updated: to for
QuickDNS updated: to for
QuickDNS updated: to for
QuickDNS updated: to for
QuickDNS made 7 updates to your C:\Windows\System32\drivers\etc\hosts file.

If you don’t see any output and you invoked with the shortcut quickdns.jar instead of java.exe -jar quickdns.jar, chances are you have *.jar associated with javaw.exe instead of java.exe. javaw.exe hides output.


Make a back up copy of C:\Windows\system32\drivers\etc\hosts.. The hosts. file is fairly fragile and mysteriously becomes corrupted fairly often. Just copy your backup onto the damaged C:\Windows\system32\drivers\etc\hosts. and run QuickDNS. If that fails, reboot and repeat.

Windows 10

QuickDNS does not work under Windows 10 unless the bat file that invokes it has the run as administrator option. This is because Windows 10 now locks the hosts. file as a system file.

Acquiring QuickDNS

1.1 2016-05-31 free Java
more infoprecismanualscreenshotbrowse source repository
for the current version of QuickDNS.
Refreshes IPs in hosts. file.
download 177K zip for QuickDNS Java source, compiled class files, jar and documentation to run on your own machine as an application.

Runs on any OS that supports Java e.g. W2K, XP, W2003, Vista, W2008, W7-32, W7-64, W8-32, W8-64, W2012, W10-32, W10-64, Linux, LinuxARM, LinuxX86, LinuxX64, Ubuntu, Solaris, SolarisSPARC, SolarisSPARC64, SolarisX86, SolarisX64 and OSX.

First install the most recent Java.

To install, extract the zip download with WinZip, (or similar unzip utility) into any directory you please, often J:\ — ticking off the use folder names option.

To check out the corresponding source from the Subversion repository, use the TortoiseSVN repo-browser to
access quickdns source in repository with [Tortoise] Subversion client on

After you have installed the jar, you can run it as an application. Type:

java -jar J:\com\mindprod\quickdns\quickdns.jar parms

adjusting as necessary to account for where the jar file is.

download ASP PAD XML program description for the current version of QuickDNS.

$1989.00 US donated so far. If the CMP utilities solved your problem, please donate a buck or two, or donate to one of the charities featured in the footer public service ads throughout the website and get a tax receipt.

QuickDNS is free. Full source included. You may even include the source code, modified or unmodified in free/commercial open source/proprietary programs that you write and distribute. Non-military use only.
Ace Utilities
hosts. file details
TweakDUN student project

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