Restore Default Apps for File Type Associations in Windows 10
If Windows 10 keeps opening files in the wrong program—or you changed an association and want to undo it—you can restore the default apps for file type associations in a few clicks. This article explains exactly how to reset associations for individual file types, for all apps at once, and how to fix common problems where the reset doesn’t stick.
What Are File Type Associations?
File type associations link a file extension (like .pdf or .jpg) or a protocol (like MAILTO) to a specific app. When you double-click a file, Windows looks up the association and launches the assigned program. Windows 10 ships with default associations for common types—Edge for PDFs, Photos for images, Groove Music for audio—but you can change them. Over time, updates or third-party installers may override your choices, or you may simply want to start fresh.
How to Reset a Single File Type Association
If only one or two file types are misbehaving, you don’t need to reset everything. Use the Settings app:
- Open Settings (Win + I) and go to Apps > Default apps.
- Scroll down and click Choose default apps by file type.
- Find the extension you want to change (e.g., .pdf).
- Click the current app icon next to it, then select the app you want from the list. If the app isn’t listed, click More apps or Look for an app in the Microsoft Store.
This changes the association immediately. To revert to Windows’ built-in default, click the Reset button at the top of the Default apps page—but note that resets all associations, not just one.
How to Reset All Default Apps at Once
Windows 10 provides a single button to restore every file type and protocol to its original Microsoft default. This is useful after installing a program that hijacked many associations (some PDF readers and media players do this).
- Go to Settings > Apps > Default apps.
- Scroll down to the Reset to the Microsoft defaults recommended by Windows section.
- Click the Reset button.
- Confirm when prompted.
This resets all associations for file types, protocols, and app defaults (like email and maps). It does not uninstall any apps; it simply clears your custom choices. After resetting, you’ll need to re-assign any programs you prefer for specific file types.
Using the Control Panel for More Control
The Settings app covers common associations, but for finer control—like changing the icon or choosing a different app for the same extension—use the classic Control Panel:
- Open Control Panel (search for it in the Start menu).
- Click Default Programs > Set Associations.
- Select a file type from the list and click Change program.
This opens the same app picker as Settings, but the list also shows protocols and lets you see the current handler for each. It’s especially handy if you want to check what app currently owns a rare extension.
Common Problems and Fixes
Sometimes the reset doesn’t work as expected. Here are typical issues and their solutions:
- The reset button is greyed out. This happens if you’re using a local account without admin rights. Sign in with an administrator account or contact your IT department.
- After reset, files still open in the wrong app. Some apps (like Adobe Reader) set themselves as the default during installation and may override Windows’ choice. Check the app’s own settings—many have an option like “Make Adobe Reader the default PDF viewer.”
- The file type isn’t listed. Rare or custom extensions may not appear in Settings. Use the Control Panel method, or right-click the file, choose Open with > Choose another app, and check “Always use this app.”
- Associations keep reverting after a Windows update. Windows may reset associations for security reasons if the app is flagged as incompatible. Re-assign the association after the update, or check if the app has an update that fixes compatibility.
Command Line and PowerShell Alternatives
For power users, the assoc and ftype commands in Command Prompt can display or modify file type associations. For example, assoc .txt shows the current handler, and assoc .txt=txtfile sets it to the text file type. However, these commands work with file types, not directly with app names, and are less intuitive than the GUI. PowerShell can also reset associations using the Get-ItemProperty and Set-ItemProperty cmdlets on registry keys, but that’s advanced and error-prone—most users should stick with Settings.
Why Windows 10 Sometimes Ignores Your Default Choice
Windows 10 uses a system called “default apps” that separates the app that handles a file type from the app that opens it. If you set a default app but the file still opens in another program, it’s often because the file type is also associated with a “protocol” or a “file type” that the app registers separately. For example, a browser might register both http and .html. You may need to change both under Choose default apps by file type and Choose default apps by protocol.
Frequently Asked Questions
Will resetting default apps uninstall any programs?
No. Resetting defaults only changes which program Windows uses to open files. All installed apps remain on your system.
Can I reset only one app’s associations without affecting others?
Yes. In Default apps, click the app name under a category (like “Email”) and choose another app, or use the per-file-type list to change individual extensions. There’s no per-app reset button, but you can manually change each association.
Why does the reset button not appear in my Windows 10 version?
The reset button is present in Windows 10 version 1703 and later. If you’re on an older version, update Windows. If the button is missing on a newer version, it may be hidden by a Group Policy—check with your system administrator.
Does resetting defaults affect my installed apps’ settings?
No. It only changes file type associations. Your apps’ internal settings, preferences, and data are untouched.
How do I stop a program from taking over associations during installation?
During installation, look for checkboxes that say “Set as default for [file type]” or “Associate with [file type].” Uncheck them. Some apps also have a setting in their preferences to “Check for default” at startup—disable that.
Can I export or back up my current associations before resetting?
Not directly through Settings, but you can use the registry editor to export the HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts key. This is advanced and requires care—editing the registry incorrectly can cause problems.
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