There are hundreds of different kinds of files on your computer including images, videos, music, text documents, executable applications and much more. Each file stores different information in different ways and can only be opened by certain programs. Windows takes the potential confusion out of this system by associating certain programs to certain file types right out of the box. While your default associations will work for most programs, you'll undoubtedly want to change a few as you try out alternative applications and find new favorites. Read on and we'll show how to change file associations in Windows 7 and Windows 8.
How to Change File Associations by Program
The most efficient way to change file associations is by selecting a default program. This tells Windows that you want a certain program to be associated with all the file types it can handle.
To do this in Windows 8, search for "Default Program" on the Start screen and click or tap "Default Programs."
In Windows 7, you can search for "Default Programs" in the Start Menu search box.
While searching is faster, you can also find the appropriate page in the Control Panel, both in Windows 7 and 8: Go to "Programs - Default Programs - Set Default Programs". Regardless of which version of Windows you're using, the following steps are the same.
Once you find the "Set Default Programs" utility, select an application from the list on the left side of the window.
To make that program the default, thus changing the file associations for all file extensions the program is equipped to handle, click or tap "Set this program as default."
If you'd like to change only a specific extension, click or tap "Choose defaults for this program."
The screen that opens displays a list of all file extensions your selected program can open. Browse through the list and select any file types you want to associate to your chosen program. When you finish, click or tap Save.
How to Change File Associations by File Extension
While changing associations by program is efficient, it's not the only way to do the job. You can also change file associations by file extension.
To do this in Windows 8, search for "file type" on the Start screen, select Settings and then click or tap "Make a file type always open in a specific program."
In Windows 7, search "file association" in the Start Menu search box and click "Make a file type always open in a specific program."
In Windows 7 or 8, you can find the same utility in the Control Panel: "Programs - Default Programs - Set Associations". To change a file association, scroll through the list of extensions to find the one you'd like to change.
Select your extension and click or tap "Change Program."
In Windows 8, select the program from the window that opens. If you don't see the program you'd like to use, click or tap "More options."
This will expand the list of programs. If you still don't see what you want, click or tap "Look for another app on this PC" to find your program's executable in File Explorer.
In Windows 7 the procedure is about the same, it just looks a bit different. You can select your program from the window or click the down arrow next to "Other Programs."
This expands the list of programs. If you still don't see what you want, click or tap Browse and find your program's executable in Windows Explorer.
Click OK when you're done.
Open a File in an Unassociated Program With or Without Changing the File Association
Your default program will likely be what you want to open most of the time, if it weren't you'd have changed it by now. However, there will be times when you want to open a file in a different program. For example: most of the time you'd want an AVI to open in a media player so you can view it, though sometimes you might want to open an AVI in a video editing application. The following procedure allows you to open an alternate program and choose whether or not to change the file association.
The easiest way to do this is to find the file you want to open in the File Explorer. Right-click or long-press the file name to open a context menu, select "Open with." This menu is accessible in both Windows 7 and Windows 8.
In Windows 8, you can find the same "Open with" menu on the File Explorer's ribbon interface. Select the Home tab and click the down arrow on the open box.
Regardless of how you get to the menu, if your program appears in the list and you click it, you won't change the file association. If you want to pick a program that isn't on the list, or you want to change the file association, click or tap "Choose default program."
In Windows 8, this gets you to the same list shown in the previous section. The only change is the inclusion of the checkbox at the top. If you want the selected program to be the new default for the file's extensions, select "Use this app for all ### files." If you just want to open the program, deselect the checkbox.
Similar to Windows 8, Windows 7's program selection screen is the same as before with the addition of the checkbox. This time you'll find it in the bottom of the window. Make your selection and click OK.
How to Change File Associations using a File's Properties Dialog
While we've covered the most common ways to change a file association, there is one more option that may prove useful in odd situations.
Right-click or press and hold a file in File/Windows Explorer and click or tap Properties in either Windows 7 or 8. In Windows 8, you can also choose to select a filename and click Properties from the Home tab.
Once in the Properties dialog, click or tap Change from the General tab. This will open the program selection window you've seen in previous sections.
In Windows 8, simply select your new default program from the list.
In Windows 7, make your selection and click OK.
Now that we've taken the mystery out of changing file associations, you should have no trouble selecting which programs open which files. Make sure you pick the program you use most to make things more efficient, but don't worry too much as you can always pick your program from the File/Windows Explorer.
If you have any additional questions regarding file associations in Windows 7 or Windows 8, feel free to leave them in the comments below.