CertiGuide to A+ (A+ 4 Real)  9  Chapter 1: What are Operating Systems and How Do They Work?       9  Operating System Features            9  Explorer: Understanding the Structure

General Folder Options 1 The Control Panel

Next, we need to understand how Explorer ‘knows’ how to handle different types of files. For example, how does it know to open up Notepad instead of Microsoft Word when a user double clicks on a text file? Understanding this process is extremely important, as rogue applications can sometimes take over parts of this process and cause files to be loaded incorrectly.

The system used by Windows to manage this is called “file associations”, and is configured from the Explorer options dialog. Select the “Folder Options” item from the Tools menu again, and select the “File Types” tab. After a brief delay, several hundred items will appear in the window.

As a practical example, locate the TXT extension in the scrolling window (as highlighted in the screenshot above). The lower half of the dialog shows some details about the file extension you have clicked. To view the actions associated with this extension, click the “Advanced” button:

The window that appears lists all actions associated with this file extension. One of them is highlighted in bold; in this case, “open”. This signifies the default action that will occur when this type of file is double- clicked in an Explorer window. Click on “Open”, and click the “Edit” button. Figure 58 will appear.

As the text says, this dialog shows the default application used for the action we are editing – in this case, Notepad.exe is quite reasonably the default editor for TXT files. If desired, this application can be changed to another text editor (for example, Microsoft Word). For now, click Cancel on all the open windows.

Every file type that can be opened from an Explorer window has an entry in this file association list. If double clicking a file does not open it in the desired application, this is the location to alter its behavior. Remember that applications are associated with file extensions, and not vice versa.

General Folder Options 1 The Control Panel