Library Notes

Popup blockers disable any popup, pop-over, or pop-under windows from displaying while using a web browser such as Internet Explorer or Firefox. They are popular with users because they block unwanted popup advertisements from displaying. However, because popup blockers block all popups, they can also disable helpful popup windows from opening as well. For instance when you click on a full-text article link in Ovid MEDLINE a new window will open up. Many of the current popup blockers installed will block this window.

Interent Explorer popup blocked example.
The "Pop-up blocked..." message may display
when a popup has been blocked in Internet Explorer.

Popup blockers come in many different forms. Some popup blockers are built into a browser. Internet Explorer running on a Windows XP Service Pack 2 (SP2) machine and Firefox both come with popup blockers that are turned on by default. Safari, a popular browser for the Mac, comes with a popup blocker but it is not enabled by default. Other popup blockers are created by a third party that you can download and install on your machine. Some of the most popular browser toolbars, such as Google toolbar and Yahoo! Toolbar, have a built-in popup blocker. Some ISP specific browsers such as AOL include built-in popup blockers while other ISP's, like Earthlink, have toolbars you can install that will block popups. There are also products available for sale that you can purchase and install that will block popup windows.

So how do you know if you have a popup blocker installed on your machine? If you notice that you have had less popups display while you are browsing the Internet there is a good chance that you have popup blocking software. If you are using the Firefox browser you most likely have a popup blocker because it comes enabled by default. If you use Internet Explore on a Windows XP/SP2 machine you most likely have a popup blocker because it too comes with a popup blocker enabled by default. There are other signs that you have a popup blocker. In the case of Internet Explorer, Safari and Firefox a message will usually display under the toolbar that says something like “Popup blocked”. A dialog box may also display that informs you that a popup window is being blocked. Finally an icon such as this may display in the footer of the browser that indicates a popup has been blocked.

Each popup blocker works differently. In most cases you do not need to disable or uninstall popup blockers to view legitimate popup windows. With a few simple steps you can configure your popup blocker to allow legitimate popups to display. Listed below you will find links to some of the most popular popup blockers and directions on how to configure them to allow legitimate popups while still stopping the annoying popup advertisements from displaying.

Popular Popup Blockers:

Google Toolbar: The Google toolbar help section can be found at: http://www.google.com/support/toolbar/bin/topic.py?topic=116
Internet Explorer: Instructions for configuring the Internet Explorer popup blocker can be found at http://www.microsoft.com/windowsxp/using/web/sp2_popupblocker.mspx
Mozilla Firefox: Instructions for configuring the Firefox popup blocker can be found at http://www.mozilla.org/support/firefox/options#webfeatures