A D   M A D

  Browsing the web can often be an experience of searching for content among advertisements and waiting for ads served up remotely from various domains. There is an easy [and free] way to eliminate many of these ads with the added benefit of speeding up the serving of web pages; the "HOSTS" file can be used as a tool to block these ads, and it can be customized by each user to suit their browsing habits.

THE HOSTS FILE
  The Hosts file shows the IP address [in the form of xxx.xxx.xxx.xxx] and name of various domains. Generally, if a domain has a constant IP address browsing is speeded up as Windows will consult the Hosts file first when translating domain names to IP addresses. In the Windows folder, there is a file named "Hosts.sam" [meaning sample] file. The sample file shows an example of an IP address with a domain name and directions on how to use a HOSTS file; the items which are preceded by the "#" sign are for explanation only.
Using the Hosts File to Block Ads
  There is an IP address reserved for all local computers [yours and mine] which is the same for everyone; that address is 127.0.0.1. Since Windows will look in the Hosts file first to translate a domain name to an IP address, if the domain names of advertisers are listed in your Hosts file with the IP address of 127.0.0.1, then Windows will, of course, not find the real IP address of the advertiser and no advertisement will be sent to you. When you browse to a web page which has ads from the domains listed in your Hosts file, the web page will show one to several blank spots where the ad would be and Windows won't miss them or wait for them. And, you, the surfer, will be served up content without the wait for and clutter of ads.
Making a HOSTS File
  1 - Find the Host.sam file in your Windows folder. [If the extension does not show, open Windows Explorer; on the Menu Bar, select "Tools/Folder Options/View Tab". Uncheck "Hide file extensions for knowm file types."]
  2 - Copy/paste it back into the Windows folder.
  3 - Rename the "copy of hosts.sam" file to "Hosts" [no quotes]. Notice that there is no extension. Windows will complain about renaming it but ignore the nag.
  4 - The Hosts file can be opened & edited with any text editor such as Notepad.exe. Don't edit it with a word processor such as Wordpad.exe. Fortunately, there already exists lists of common ad serving domains neatly compiled with the 127.0.0.1 address in a Hosts friendly format. One such list can be found at http://www.ecst.csuchico.edu/~atman/spam/adblock.shtml . Copy, then paste the list of ad server domains with the 127.0.0.1 IP addresses from that webpage into your Hosts file.
Customizing Your HOSTS File
  Your new Hosts file will now block the major ad serving domains from placing ads on the web pages you access. However, depending on what software you use [such as free ISPs] and where you browse, many ads will still get through. To add your own entries to the Hosts file, use IE4/5's cache of browsed files; it is a gold mine of ad server domain names. The name of the cache folder is Temporary Internet Files [AKA TIF].
  1 - First, clear the TIF, from "Internet Options/General Tab/Delete Files". Check "Delete all offline content", select OK twice.
  2 - Put a shortcut to the TIF and the Hosts file on your Desktop.
  3 - After browsing various websites [especially, the larger, commercial ones] with one or more of your ISPs and signing off, open the TIF shortcut to find ads which may have appeared on webpages you accessed. [Note: Set your TIF view to "Details" by selecting View on the Menu Bar.] Ads are usually "gif" files whose URLs appear to be from ad servers. The domain names of these ad servers can be copied from the Address Bar if you open the "gif" or from "Properties" when right clicking on the "gif". Paste just the domain name, not the entire file name into the Hosts file after entering 127.0.0.1 and a space. Each entry in the Hosts file should be on a separate line. [Note: If, when trying to open a TIF file, you receive a message that "Running a system command on this item might be unsafe. Do you wish to continue?", select Yes. If you get a message that "Your current security settings do not allow you to perform system commands on this item.", then enable or prompt "Launching programs and files in an IFRAME" in Internet Options/Security Tab.]
Blocking Ad Servers

  Browsing is speedier, and content is served faster. Some Ad servers have been found to collect data about the browsing habits, preferences, and personal information of the surfer; do not surrender or compromise your privacy or best interests to those who would use you for their own ends. Periodically, examine your Cache [TIF] to update your Hosts file. Within the first day of adding the list cited in the above link, I added over 50 ad servers. If you are a user of the free X-SetUp Tweaking Utility, there is a plugin on my Plugin Page which will assist in working with TIF files; it will allow you to "read" Cache files by setting IFRAME preferences if warnings occur. Another free useful utility, which will allow you to place Notepad [or any other application] in the right click [context] menu of both the HOSTS file and its shortcut, is Multilaunch . Here's how to use NOTEPAD to open NO EXTENSION files.

More Ad Blocking Strategies

  1 - If you use AOL and have placed Ad Server domain names with 127.0.0.1 in your Hosts file, browse the web OVER the AOL shell; in other words, open your browser as a standalone application when you want to access websites that use advertisements.
  2 - Some websites serve ads from their own domains often with other graphics. One example [without naming names], is a news-type website whose main page consists of about 26kb [2 files] of text content and 107kb [46 files] of graphics [which are a mixture of ads and standard navigation or identification pictures]. Loading the page with graphics turned on is materially slower than loading the same page with graphics turned off. [Graphics in IE can be turned off by unchecking "Show Pictures" on the Advanced Tab of Internet Options.]
  3 - Turning off graphics solves much of the problem of ad clutter, but it is overkill as all pictures are turned off when another website is accessed. You can turn graphics back on by checking "Show Pictures", but this can become a time consuming and clumsy approach. You can solve this problem by putting some sites in a graphics permitted category and other sites in a no graphics category as follows:
   a - Start a browsing session with graphics turned on, that is with the "Show Pictures" option checked.
   b - When you want to access a website that is known to serve its own ads from its own domain [examining the TIF periodically will reveal the origin of the ads], run a Registry entry to turn off graphics & open a separate instance of your browser. Now you will have two instances of IE open; one will show graphics [it will be on the left side of the Taskbar]; the other will show no graphics [it will be on the right side of the Taskbar].
   c - The above graphics on & off works because the first instance of IE is "looking at" a Registry that says to Show Pictures while the second instance of IE is "looking at" a Registry thats says do not Show Pictures. With these two instances of IE open, you can browse in graphic & non-graphic mode by alternating between the left side [graphic] & right side [non-graphic] browsers. Here are the Registry Entries in a zip file which can be used to turn graphics off [pixsoff.reg] and to turn graphics on [pixson.reg]. Unzip them to your location of choice for easy access.
  4 - Some ads [gifs] are served from a domain name that looks like http://xxx.xxx.xxx.xxx where "x" is a number. Putting these numbers in the HOSTS file is useless; since Windows gets the IP address from the web page, it doesn't need to refer to the HOSTS file. When you spot these kinds of URLs in the Cache, make a note of which website is using IP address served ads. To defeat these ads, use the same "pixs-off" strategy for domains that mix ads with standard graphics.

Redirect

  Some websites redirect you to another page whether you want to go there or not. One such website is Hotmail; when the visitor logs off from Hotmail, the MSN home page [www.msn.com] is served up. To stop this behaviour, one can put www.msn.com into the HOSTS file; a "The page cannot be displayed" message will appear.

Blank Message

  With Internet Explorer & an active HOSTS file, a typical blocked ad will return a red X . When an entire domain is blocked via the HOSTS file such as "www.doubleclick.net", browsing to that location will return "The page cannot be displayed" message. This same message will appear [at least partially depending on the size allocated to the ad] if that domain is embedded [such as through layering or Iframes] on a webpage of another domain [e.g. www.pcworld.com]. This message is embedded in the file "shdoclc.dll" [in the Windows\System folder] as common HTML code; to make this message less verbose [and annoying], open a copy of shdoclc.dll [pasted into a non-Windows locale] with a word processor; browse to the sections that hold "The page cannot be displayed" message and other text with an Edit/Find operation; change the font color from "black" to "white". It is strongly advised to save the original "shdoclc.dll", rename it to something like "shdoclc0.dll" [I prefer the 0 (zero) to denote original]; then copy your revised copy of "shdoclc.dll" to the Windows/System folder. NOTE: If you had been previously working with IE, Windows may complain about the rename & paste operations; a reboot may be necessary. Also the rename & paste operations can be made from native MS-DOS or from another OS if you dual boot.

The new error message will show small icons with the red links for "Refresh", "Detect Network Settings", & "Back" still intact & functional; the background will be white. NOTE: If your system experiences problems, replace the original shdoclc.dll. Some problems have been reported with right click [context] menu functionality after the font color changes were made.
If a white background is not to your liking, you can change the "bgcolor" of the relevant message sections to "black" from "white" and not change the font color. This will give a black backgound with the red links still intact & functional.

Whether you prefer the white or black background, another change can be made to the Title Bar message which appears when the Hosts file blocks a domain. The standard Title Bar message is "Cannot Find Server"; browse to that phrase and change it to "Domain HOST Listed".

For more resources about the Hosts file and Adware, see the following links:
MAP YOUR HOSTS & NO ADS THANK YOU!
The above links are also included in TIPS95.TXT, part of
AXCEL216's Win9x/2000 + DOS 7.xx Tricks + Secrets files [W95-11D.ZIP, freeware]
at http://user.aol.com/axcel216/95.htm

Download a copy of this webpage in PDF format.
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