How to change app protocol associations in Windows 11

Generate a Default App Associations XML File

You can generate a default app associations XML file in Windows 11 by using the Deployment Image Servicing and Management tool from an elevated command prompt. This export command captures your current file type and protocol mappings so you can save and modify them for deployment across multiple computers.

1. Open the Start menu ⊞, type cmd, right-click Command Prompt in the search 🔍 results, and select Run as administrator.
2. Type the export command using the DISM (Deployment Image Servicing and Management) tool to capture your current settings. Run the following command, replacing the path with your desired save location:
   

   dism /online /Export-DefaultAppAssociations:C:\temp\DefaultAssociations.xml

3. Press Enter and wait for the operation to complete successfully.
4. Navigate to C:\temp\DefaultAssociations.xml using File Explorer 📁 to verify that the XML file was created.

Modify the Default App Associations XML

You can modify the default app associations XML file using Notepad to change preferred handlers for specific file extensions and protocols before you import the settings ⚙️ to other computers. Editing this file lets you control which programs open specific links and files across your entire system.

1. Right-click your exported XML file and select Open with, then choose Notepad.
2. Locate the specific protocol or file extension entry you want to change within the XML structure. Each entry uses identifier tags specifying the extension or protocol name alongside the corresponding AppUserModelID of the target application.
3. Modify the application identifier string to point to your desired handler. Ensure you retain the exact syntax of the surrounding XML tags to prevent parsing errors during import.
4. Click File and select Save to store your changes.

Import Default App Association Settings

You can import default app association settings on a running Windows 11 installation by running a specific command prompt tool that points to your customized XML file. This action instantly updates your system-wide protocol and file type mappings to match your preferred application choices.

1. Open the Start menu ⊞, type cmd, right-click Command Prompt, and choose Run as administrator.
2. Run the import command via the DISM utility, pointing it to your modified XML file location:
   

   dism /online /Import-DefaultAppAssociations:C:\temp\DefaultAssociations.xml

3. Press Enter to apply the associations.
4. Restart your 🔄 computer to ensure all running processes and shell components recognize the updated protocol mappings.

Add or Remove Default Application Association Settings to a Windows Image

You can add or remove default application association settings to a Windows image by mounting an offline Windows image file and using the Deployment Image Servicing and Management utility to inject your custom XML file. This process configures default app choices for custom operating system deployments.

1. Open Command Prompt as an administrator and mount your Windows image to a temporary directory using DISM:
   

   dism /mount-image /imagefile:C:\images\install.wim /index:1 /mountdir:C:\test\offline

2. Import the association file into the mounted image:
   

   dism /image:C:\test\offline /Import-DefaultAppAssociations:C:\temp\DefaultAssociations.xml

3. Review the applied settings or unmount the image once configuration finishes.

Importing settings directly into an offline image ensures that every device deployed from that image immediately respects your protocol and file extension preferences without requiring post-installation scripting.

Review the default app association setting in an image

You can review the default app association setting in an image by running a query command in Command Prompt that points to your mounted Windows directory. This check lets you verify that your file type and protocol mappings are correct before you finalize your deployment package.

1. Open Command Prompt as an administrator.
2. Run the query command pointing to your mounted directory:
   

   dism /image:C:\test\offline /Get-DefaultAppAssociations

3. Review the output list in the command window to verify that your protocols point to the intended applications.

Remove default app association settings

You can remove default app association settings from a mounted Windows image by running a targeted removal command in Command Prompt. This action completely clears any previously injected association lists so you can start fresh before finalizing your custom operating system build.

1. Open Command Prompt as an administrator.
2. Run the removal command targeting your mounted directory:
   

   dism /image:C:\test\offline /Remove-DefaultAppAssociations

3. Press Enter to strip the custom association file from the image.

Unmount the Windows image

You can unmount the Windows image and save your changes by running the unmount command with the commit switch in Command Prompt. This action safely closes the temporary directory and writes all your app association modifications directly into the offline image file.

1. Open Command Prompt as an administrator.
2. Run the unmount command with the commit switch:
   

   dism /unmount-image /mountdir:C:\test\offline /commit

3. Wait for the progress bar to reach 100 percent and verify that the mount directory is empty.

What to do next

Test individual URL schemes or configure group policies to lock down user modifications across your environment.