Working with File Types and Programs
One of the more frustrating aspects of using a PC is when you click or tap on a file to open it only to find that it doesn't open in the program you were expecting it to. This is especially irksome when a given file used to open in a familiar program but then suddenly and for no apparent reason opens in a different one.
In this tutorial, we'll explore how Windows determines which program automatically opens your files and how to check in advance which program is configured to open which types of file. This is known as the default program. We'll also outline how to change the default program for a file type and then override that default for specific instances when you want to open a file in a different program than usual.
PROGRAMS VS. APPS
Before we get started, let's talk about the difference between a "program" and an "app". Strictly speaking, there isn't any-both are a piece of software that you use to open a file, although the latter term is more often used to refer to programs downloaded from Microsoft's Windows Store (and which have a modern, touchoriented interface). Microsoft uses both of these terms in Windows, and not entirely consistently, either. For the sake of clarity, we're going to refer mainly to "programs" in this tutorial, but be aware that the terms are essentially synonymous.
File Extensions
So how does Windows decide to automatically open file x using program y? Put simply, it looks at the type of file that you're opening-which is denoted by a three- or- four character suffix called an extension-and then starts up the program that's been defined as the default program for that file type.
Table lists some frequently encountered file extensions and types.
Table: Common file extensions and types
Extension Type Extension Type .docx Microsoft Word .gif Graphical Interchange Document Format image .xlsx Microsoft Excel .jpg JPEG image Spreadsheet .pptx Microsoft .mp3 MP3 audio PowerPoint Presentation .pdf Adobe Portable .mp4 MPEG-4 video Document Format .txt Plain text document .mov Apple QuickTime movie
Under normal circumstances, file extensions are hidden from view in File Explorer, but it's easy to make them visible. Click or tap the View menu and check the box labeled File name extensions; you'll see each file's extension displayed to the immediate right of its name. Checking this box makes file extensions visible not just in File Explorer but also in any other area where you view file listings, such as on the Desktop or when opening/saving files within programs.
File Associations
As a rule, you won't typically need to make file extensions visible because File Explorer's "Type" column and/or the file's icon will normally indicate what type of file you're dealing with. But, visible or not, file extensions are still important because they are what allows Windows to define a relationship between a particular type of file and the program (or programs) that can open that file.
This relationship is known as a file association, and the most important file association in Windows is the aforementioned default program, because it determines which program will automatically open a file when you click or tap on it.
Default programs can sometimes change unexpectedly, however. Often when you install a new program-or update an existing one-that's capable of opening a particular type of file, the program configures itself to automatically open every file type it knows how to handle. As it happens, most programs do give you the opportunity to review and override these changes during the install process, but they're often accepted without close scrutiny because of haste or inattention. This is typically how default programs get changed without anyone necessarily realizing that it has happened.
Fortunately, Windows lets you configure default programs and file associations so that you can always open the type of file you want with the specific program you want.
Configuring Default Programs
To view and configure default programs in either Windows 8.1 or Windows 10, search for and select "Default Programs", then choose the option labeled "Set your default programs".
After a few seconds of load time, you'll see the window, listing all of your installed programs along the left pane. When you highlight a program in this left pane, you'll see configuration information about it in the right pane, including the name of the program, which company makes it, and, in some cases, a brief description of what the program does.
Your programs should be listed in alphabetical order, but you can switch to reverse alphabetical order by clicking or tapping the heading labeled "Programs".
Beneath this information, a line reports how many defaults the program is configured for. In other words, a program that reports that it "has 2 out of 5 defaults" means that it is associated with five different file types but is configured as the default program for only two of them.
To make the highlighted program the default for all of its associated file types, just click or tap "Set this program as default" and you'll see the aforementioned line change to "This program has all its defaults".
Conversely, to view and/or selectively change individual defaults, click or tap "Choose defaults for this program" to display a window. Then check the additional file extensions that you want the program to be the default for and click or tap Save.
Notice that if a file extension is already checked, you can't uncheck it because that would eliminate the file's default program without specifying a new one. To change the default program for a specific file extension, see the next section.
Configuring Default Programs by File Extension
The process that was just outlined is intended for situations in which you have a favorite program and want it to be the default for every file that it can open, or when you want a particular program to open specific additional file types that does not currently open. Put another way, once you've specified the program, you can specify the file extensions that it will automatically open.
If, by contrast, you approach the situation from the opposite perspective-you have a particular file type in mind and you want to choose a view or change the default program for it-the process is slightly different.
You still begin by searching for and running "default programs", but then you choose "Associate a file type or protocol with a program" to display the window, which lists file extensions, descriptions, and the current default program for each.
You'll find the list of file extensions arranged alphabetically just like the program list, but the file extension list is considerably longer as it will contain dozens if not hundreds of obscure or unfamiliar file extensions.
Also, be aware that a separate alphabetized list of protocols (which governs how Windows handles different kinds of Internet links in a Web browser or in certain programs) follows the file extension list, so that's what you'll be looking at if you scroll all the way to the bottom.
To change the default program for a given file extension, highlight it and click or tap the Change program button. Doing this with the .pdf file extension gives us the option to change the default program from Adobe Acrobat Reader DC to Microsoft's PDF Reader, which is built into Windows 8.1.
(Notice that the options presented will vary depending on which file extension you select, which programs you have installed, and even which version of Windows you are using.)
Selecting More options, (called More apps in Windows 10), will display additional program choices for opening the file, but those extra choices won't necessarily all be appropriate for the file. For example, for a .docx file (Microsoft Word Document), More options/apps will give you the option to open it in Microsoft Paint, an image editor, or Windows Media (audio/video) Player, neither of which were designed to open Micosoft Word documents. Suffice it to say that, as a rule, it's best to stick to the programs initially offered and avoid More options/apps unless you have a specific reason to choosing a different program.
HOW DO YOU WANT TO OPEN THIS TYPE OF FILE?
Sometimes when opening a file you will see a popup window in the upper right corner of the screen, which is Windows proactively asking if you want to change the default program for that file type. This typically happens the first time that you try to open a particular file type on a PC, or after installing a new program that can open that file type (which gives you additional choices for a default program).
Opening a File with a Program Other than the Default Program
Even after you've chosen a preferred default program for a particular file type, there may be occasions when you want to open a given file in a different program without actually changing that default program. For example, you'll typically open video files in a player program, but if you want to edit a video you'll want to open it in an editing program instead.
Fortunately, Windows makes it easy to choose the program that you want to use each time you open a file. Just right click or long tap the file and choose "Open with" to display a list of appropriate programs. Select the program that you want and the file will open in that program without changing the default program.
The Choose default program option offers an alternative method to "Choosing default programs by file extension" described earlier. Select this item and you'll see a window, allowing you to specify a new default app. Notice the check mark next to "Use this app for all...".
OPEN WITH IN WINDOWS 10
In Windows 10, the Open with menu's Choose default program option has been changed to Choose another app. You can still change the default program from here, but you must be sure to check the box labeled "Always use this app to open...".
Opening a File When You Don't Have the Right Program
If you try to open a file for which you don't have the correct program. This allows you to look for the right program in the Windows Store.
For example, we're attempting to open a file with an .mpp extension, which was created in Microsoft Project and which we don't have installed on our PC. You could use the Look for an app in the Store option to find one, but another-and arguably better-option is to do an online search for the file extension or file type to find a program that will be able to open it.
Doing your own search is preferable because the Windows Store only has a limited number of programs/apps available, all of which use a modern, touchcentric interface (which you may or may not want). In addition, you need a Microsoft account to download anything from the Windows Store. In contrast, you'll almost always have more and better options when you search for a program yourself.
