Using the Hosts File to Block Content

by Barry Dysert
(last updated January 9, 2017)

2

Your Hosts file is an important system file for network communications, and it can be used as a rudimentary method for blocking Internet sites. Given the fact that the IP address 127.0.0.1 always points to your local computer, you can modify your Hosts file so that a website that you want blocked is mapped to that IP address.

Say that you wanted to block "www.facebook.com". Modify your Hosts file so that it contains this line:

127.0.0.1     www.facebook.com

Now if you direct your Web browser to "www.facebook.com" you will instead be directed back to your local computer. The reason this happens is that in parsing the domain name (www.facebook.com) your computer looks to the Hosts file for resolving the DNS address instead of to an external system which would return the real IP address for Facebook.

The ability to use a Hosts file has led some folks to develop rather complete blocking solutions for individual computers. One popular one is available at the following page:

http://winhelp2002.mvps.org/hosts.htm

Basically what is offered is a copy-and-paste way to block sites through your Hosts file, which can be simple and effective.

There is one caveat with using a solution such as the MVPS HOSTS file: It can have some unexpected results. One rather personal example is that the MVPS HOSTS file blocks anything related to a popular e-mail fulfillment service known as AWeber. It just so happens that WindowsTips (and other Tips.Net publications) utilizes AWeber for publishing newsletters. That means that on a system that includes, in its Hosts file, information copied and pasted from the MVPS HOSTS file, the user won't be able to click any of the links in the WindowsTips newsletter or any other Tips.Net newsletter. This occurs for reasons already discussed in this tip.

The moral of the story is that if you decide to use a Hosts-file-based solution provided by someone else, make sure that you understand what is actually being blocked. (You could use the MVPS HOSTS solution, but you'll want to search through the file for any entries containing the characters "aweber." Delete those lines—there should be two of them—and you can again access any links in Tips.Net newsletters, including the links in WindowsTips.)

As noted, using the Hosts file to block content is effective, but it is rather rudimentary because (1) you could always remove this line from your Hosts file, or (2) specify the IP address in your browser, thus bypassing your Hosts file altogether.

 This tip (12875) applies to Windows 7, 8, and 10.

Author Bio

Barry Dysert

Barry has been a computer professional for over 30 years, working in different positions such as technical team leader, project manager, and software developer.  He is currently a senior software engineer with an emphasis on developing custom applications under Microsoft Windows. ...

MORE FROM BARRY

Adding and Deleting Fonts

Sometimes a document you're working on needs a font different from what comes with Windows. In such a case, a simple Web ...

Discover More

What is the Purpose of the Security Event Log?

The Security event log captures success and failure audit events when auditing is turned on. This tip explains a bit more ...

Discover More

Using Powercfg to Change the Active Power Scheme

You can easily change which power scheme is active by using the SetActive switch. This tip shows you how.

Discover More
More WindowsTips

Introduction to Microsoft Edge

Windows 10 comes with a nice replacement for Internet Explorer (which is still retained for those who need it). This new ...

Discover More

Resetting a Web Browser to Its Default Settings

We can make a lot of adjustments to our Web browser over time. If you ever want to restore your browser to its original ...

Discover More

Changing Your Internet Home Page

Regardless of the browser you use, there's a way to change its settings so that you can specify where it goes when you click ...

Discover More
Subscribe

FREE SERVICE: Get tips like this every week in WindowsTips, a free productivity newsletter. Enter your address and click "Subscribe."

View most recent newsletter.

Comments

If you would like to add an image to your comment (not an avatar, but an image to help in making the point of your comment), include the characters [{fig}] in your comment text. You’ll be prompted to upload your image when you submit the comment. Maximum image size is 6Mpixels. Images larger than 600px wide or 1000px tall will be reduced. Up to three images may be included in a comment. All images are subject to review. Commenting privileges may be curtailed if inappropriate images are posted.

What is five more than 2?

2017-05-03 16:52:31

Tom Sellers

I wish I had seen your aweber tip long ago. For weeks it caused me grief with numerous websites. Not just newsletters. I could not see my stock portfolios (on Barchart's website), or login to some internet based subscriptions I used (at stockcharts.com). I must have re-installed java dozens of times thinking that was the problem. I had even considered re-installing Windows until I ran a test and temporarily deleted my hosts MVP file. Eventually I tracked it down to aweber. I don't know how many hours of frustration this caused me. However, it would appear from the comment from Carl, perhaps the new MVP files have already addressed this problem - I was not diligent about updating the hosts file because I have some of my own custom entrys in there as well.


2017-01-09 14:52:23

Carl Bolstad

I've been using the mvps HOSTS file for years and the Windows Tips for months, and never had a problem following the links in the newsletter. I just looked at the most recent HOSTS file (12/20/2016) and found that there is an entry for clicks.aweber.com, but it is commented out, with the comment "affects newsletters". So apparently the mvps people have noticed and fixed this problem.


Newest Tips
Subscribe

FREE SERVICE: Get tips like this every week in WindowsTips, a free productivity newsletter. Enter your address and click "Subscribe."

(Your e-mail address is not shared with anyone, ever.)

View the most recent newsletter.