Plugins with Internet Explorer

Many years ago, Netscape created an option for a piece of software named a plugin.  A plugin allowed an individual to add functionality to the Netscape browser that was not present by default.  Certain programs add plugins in modern browsers when they are installed locally on a computer.  An example would be Adobe Acrobat Reader.  When it is installed on a computer, it adds a plugin for Netscape and Internet Explorer.  If a hyperlink for a PDF document is accessed, the file is opened within the browser window.

Internet Explorer introduced a concept named ActiveX.  This technology allows an application over the Internet to access a computer's local hard drive, among other features.  An ActiveX control is an executable program that can be automatically delivered over the Internet where it usually runs within a browser.  For example, if an individual accessed an online anti-virus scanning service, a dialog box would appear similar to the following image.  This window is asking if an application can be installed on the computer in question to perform the virus scan.

A similar type of box will appear if a web site is accessed that contains Flash, and it is not present on the computer.

Please keep in mind that if the Yes button is selected, some type of application will be downloaded and installed on the computer.  Some of these applications have hidden properties in addition to the stated purpose.  If a dialog box appears while using Internet Explorer, do not click the Yes button without having a good understanding of what it is asking, and what will be installed.  The default answer for any dialog box that is similar to the images above should be No.

Some web pages are more persistent than others.  For example, the following dialog box appears:

When you click on the No button, another dialog box appears such as the one below:

If this loop occurs, access the Task Manager and close all running copies of Internet Explorer.

The dialog box below is an example of an offer to upgrade your browser.  This is a method used to have someone install an application that appears to be missing from his or her computer.

Starting with Windows XP Service Pack 2, the ActiveX dialog box will appear similar to the example below.

Under the more options button, a selection is available to never install software from the publisher in question.

A small information bar may appear within Internet Explorer stating an ActiveX control is attempting to be installed, as well as a Information Bar dialog box.

Some sites now attempt to offer instructions to have an ActiveX control installed.

With Vista and Internet Explorer version 7, a "protected mode" is enabled by default.  A dialog box such as the one below should appear if an action requires the use of another application.