The quickest way to open a Windows 10 file is by double-clicking it. However, it might not open in the app that you want.

Thankfully, you can change this by altering its default app association. This determines which programs open which file types. Files with a .doc extension usually open in Microsoft Word, for example, while .xls files open in Excel. Installing a new app can alter these associations, resulting in files not opening the app you expect. Read on for how to solve this.

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Step 1: Find the file

The simplest way to change a file association is to start by finding the file in question. Right-click it and select Open with > Choose another app from the menu that appears.

1. Find the file

Step 2: Check the default app association

When the dialogue box opens, you can choose to open the file in its default app (shown as Keep using the app) or choose an alternative below Other options. If the app you want to use isn’t listed, click More apps.

2. Check the default app association

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Step 3: Find an unlisted app

If the app you want still isn’t listed — and you’re sure it’s installed — scroll to the bottom of the list and choose Look for another app on this PC. You can then browse the folders on your hard drive to find the appropriate app — click its .exe file to select it.

3. Find an unlisted app

Step 4: Make a permanent change

Whichever option you choose, this method won’t change the default file association — it will only open the file in a different app this one time. To make the change permanent, tick the box for Always use this app… in the dialogue box opened in Step 2.

4. Make a permanent change

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Step 5: Change other Windows 10 app associations

File associations are only one kind of default app in Windows 10. If you want to change which web browser opens links, for example, or which music player to use, there’s a different way to do it.

Go to Start > Settings > Apps > Default apps. When the dialog box opens, find the app type you want to change and click its entry. You will then be able to choose between any other compatible apps that are installed.

5. Change other Windows 10 app associations

Step 6: Manage advanced app association settings

If you scroll to the bottom of this list of apps, you’ll see some advanced options. Be careful changing these, as it’s easy to get confused about which file opens where. You can always click the Reset button in the dialog box to undo any changes, though.

6. Manage advanced app association settings

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