We understand how frustrating it is when it looks as if AdBlock isn't blocking ads. We want to help you understand why you might be seeing them and what you can do. In no particular order, these are the most common reasons ads aren't blocked:

  • Whitelisting (accidental or on purpose): You may have told AdBlock not to block ads on a page or site, or you may be using incognito mode or a private browsing window.
  • Circumvention: Advertising technology companies found a way to get around ad blockers.
  • Malware: You downloaded software or visited a website that secretly installed malicious software on your computer. Some useful and apparently harmless extensions can inject ads into web pages you visit, even extensions in the Chrome Web Store.
  • Acceptable Ads: Because we understand that, like it or not, ads are still the primary source of funding for websites, AdBlock allows some non-intrusive advertising to appear unless you turn this setting off. We tell you this and give you the opportunity to turn it off on the donation page that appears after you install AdBlock. If you closed that page without reading it, you may not realize that unobtrusive ads won't be blocked.
  • Filter lists: Your filter lists are out of date or you're not subscribed to the right filter lists for the website you're visiting.
  • Other: There are several other reasons ads may not be blocked. They are just as common as the ones we listed above but they don't fit into neat categories.

This article will guide you through the troubleshooting steps we go through ourselves and offer the solutions we've found. Start where we do:

  1. Make sure the ads are legitimate, not the result of malware.
  2. If the ads are legitimate, check for the things that most often interfere with ad blocking.

Step 1. Are the ads caused by malware?

If you see the same ads on every website or your browser's search page has been changed, it's probably a form of malware called "adware." Learn more about adware.

If you're seeing the exact same group of similar-looking ads on every website, then your computer has been infected by a form of malicious software called "adware." If your browser's search page has been changed to a page with ads, that's a symptom of another type of malware known as a "browser redirect virus."

Here are some examples of the kinds of malware we often see.

"Ads by Super Back-up" adware example
This is adware, malware that injects ads into web pages. Look for clues such as a group of similar ads with words like the ones we have circled in red. Other examples are "Related Deals," "Shopping Deals," "Great Deals," and "Similar Deals." (Do you see a pattern emerging here?)
"Smartshopping.com" browser redirect example
This is an example of a browser redirect virus. This type of malware "hijacks" your browser's default search page, driving traffic to the malware developer's site or redirecting your searches to websites where they’ll receive a commission or other revenue. The clues here are the site name in the address bar, the logo in the upper right corner of the page, and of course, the page full of ads.
Browser search redirect pop-up adware example
This is an example of a pop-up ad you would see if you clicked a link on a redirected search page. We know this is malware because 1) the ad popped up when we clicked a link, and 2) the pop-up has the words "powered by." "Powered by," "brought by," or just "by" followed by a name are a really big clue that you're looking at malware.
Full-page adware example
Another form of adware is the full-page pop-up, an ad that opens a new tab without your consent. This one even has its own pop-up ad!

Ad blockers can't block this kind of malicious advertising. The only way to remove the ads is to remove the malware that's causing them. Continue to instructions for removing malware from your computer.

If you see one or two ads on just one website, it's probably a legitimate ad that slipped through your ad blocker. Continue to Step 2.

Step 2. Check for common problems

Let's assume for now that the ads are not malware, and check the other most common reasons ads aren't blocked.