Fix Windows 11 Cannot Change Default Apps for File Types

Quick fix: Open Settings → Apps → Default apps, search for the file type in the search box at top (e.g., .pdf), click the current default, pick the new app, click Set default. Windows 11 changed the default-apps UI in 22H2 — now it’s per-extension rather than per-app.

You try to change the default app for PDF, MP4, or any file type. The familiar Windows 10 “default by app” UI is gone. Or you change the default, restart, and it’s back to the previous app. Windows 11 22H2 reworked the default apps system — settings are now per-extension and per-protocol, and certain Microsoft apps are stickier than before.

What causes this

Windows 11 22H2 changed the default-apps model from “set this app as the default for all its types” to “set this specific extension/protocol to use this app.” This is more accurate but more tedious — you have to set defaults per extension (.pdf, .docx, .mp4 each separately) instead of one click for an app. Microsoft also added stickier defaults for Microsoft-signed apps (Edge for PDF, Movies & TV for video) that may revert if not explicitly locked.

Method 1: Set per-extension default via Settings

The standard 22H2+ approach.

1. Open Settings → Apps → Default apps.
2. At the top is a search box: Set defaults for applications. Below it: Set a default for a file type or link type.
3. In the Set a default for a file type or link type search box, type the extension (e.g., .pdf).
4. Click the result. The current default app appears with file type info.
5. Click the current default app icon.
6. A picker appears listing alternative apps. Click your preferred app.
7. Click Set default.
8. The change is immediate. Double-click a .pdf file — opens in your new default.
9. Repeat for related extensions (.fdf, .xfdf, .pdfx for full PDF coverage).

The per-extension model is more accurate but takes more clicks for multi-type apps.

Method 2: Set defaults for an entire app at once

Use when an app handles many file types.

1. Open Settings → Apps → Default apps.
2. In the Set defaults for applications search box, type the app name (e.g., VLC).
3. Click the result.
4. The app’s page shows every file type and protocol it can handle. Each has a current default app shown next to it.
5. For each type you want this app to handle: click the current default, pick the new app (your selected one if it’s a logical choice), click Set default.
6. Tedious but precise. For VLC, you might set defaults for .mp4, .mkv, .avi, .mov, .webm, .mp3, .flac, etc.

This is the per-app approach within the new per-extension model. Good for media players.

Method 3: Set defaults via PowerShell using ftype/assoc

For scripted setup or when GUI fails.

1. Open Terminal (Admin).
2. List current associations:

   cmd /c assoc .pdf

   Shows the file type identifier (e.g., .pdf=AcroExch.Document.DC).

3. List what command is associated:

   cmd /c ftype AcroExch.Document.DC

   Shows the executable.

4. To change file association:

   cmd /c assoc .pdf=AcroExch.Document.DC

   This points .pdf at Adobe Acrobat.

5. For non-admin per-user changes, the SetUserFTA tool (free utility, github) handles per-user default app registration that Windows 11’s GUI doesn’t expose directly.
6. For policy-locked defaults across multiple PCs: use Default Apps Association XML (export from a configured PC via Dism /Online /Export-DefaultAppAssociations:"C:\path\to\AppAssociations.xml", deploy via Group Policy).

This is the right approach for IT deployment or stubborn defaults.

How to verify the fix worked

• Double-click a file of the target type (e.g., .pdf). Opens in your new default app.
• Right-click the file → Open with. The default (bold) entry shows your preferred app.
• In Settings → Default apps, search the extension. Default app shown matches your choice.

If none of these work

If defaults revert after setting, three causes apply. Edge reset for PDF: Edge updates sometimes reset .pdf default to Edge. Block this by setting registry policy at HKLM\SOFTWARE\Policies\Microsoft\Edge\DefaultBrowserSettingEnabled = 0 and similar. Microsoft app default reset: Movies & TV reclaims .mp4 on app updates. Set the policy HKCU\Software\Microsoft\Windows\Shell\Associations\UrlAssociations\<protocol>\UserChoice with the right ProgId — but this is sensitive to a hash that Microsoft uses to detect non-UI changes. Group Policy: corporate managed PCs may enforce specific defaults. Use Set Default Programs by File Extension policy via gpedit.msc for managed control.

Bottom line: Windows 11 22H2 changed default apps to per-extension — use Settings → Default apps → search extension → click current default → pick new app. Tedious but the right model.