Upload Custom ADMX Templates to Intune

Problem

Many environments run Firefox and Zoom, but Intune’s Settings Catalog does not include built-in update policies for these apps.

For Firefox, I initially wrote a proactive remediation script that checked the local version against Mozilla’s latest and auto-installed updates. It worked, but it was extra complexity to maintain.

Then I discovered ADMX imports. Upload the vendor’s policy templates to Intune and you get the same settings you’d have in Group Policy. Much simpler.

Constraints

• Windows 11
• Intune

Decision

ADMX files are XML-based Group Policy templates. They define what settings are available. ADML files are the language files that provide the UI text.

You’ve probably used these in on-prem Group Policy. The same files work in Intune.

Implementation

Common sources:

Outcome

1. Get Your ADMX and ADML Files

For Firefox:

1. Download the Firefox ADMX templates from Mozilla
2. Extract the ZIP
3. You’ll find:
   • firefox.admx - The template file
   • en-US\firefox.adml - The English language file

2. Import into Intune

1. Go to Intune admin center → Devices → Configuration
2. Click the Import ADMX tab
3. Click Import
4. Upload the .admx file
5. Upload the matching .adml file (usually from en-US folder)
6. Click Next and complete the import

The import takes a few minutes. You’ll see the status change from “In progress” to “Available”.

3. Handle Dependencies

Some ADMX files depend on others. For example, many Microsoft templates need windows.admx as a base.

If you get a dependency error:

1. Note which file it’s asking for
2. Import that file first
3. Then retry your original import

Common dependencies:

• windows.admx - Base Windows definitions
• windowscomponents.admx - Windows component definitions

4. Create a Policy Using Your ADMX

Once imported:

1. Go to Devices → Configuration → Create → New policy
2. Select Windows 10 and later
3. Select Templates → Imported Administrative templates (Preview)
4. Pick your imported template
5. Configure the settings you need
6. Assign to your groups

Trade-offs

After importing Firefox ADMX:

1. Create new policy using the imported Firefox template
2. Navigate to Mozilla → Firefox → Updates
3. Enable Application Update settings:
   • AppAutoUpdate = Enabled
   • BackgroundAppUpdate = Enabled

This tells Firefox to update automatically in the background - no scripts needed.

Example: Zoom Auto-Update Policy

After importing Zoom ADMX:

1. Create new policy using the imported Zoom template
2. Navigate to Zoom Meetings → General Settings
3. Configure update settings as needed

Verify the Import

After importing, you can check:

1. Go to Devices → Configuration → Import ADMX
2. Your template should show status “Available”
3. Click on it to see all the settings it contains

Trade-offs

• One ADML per import - You can only upload one language file. Pick en-US unless you have a specific need.
• Version conflicts - If you import an older version of an ADMX that’s already built into Intune, you might get conflicts. Check if the setting exists in Settings Catalog first.
• Preview feature - Imported Administrative Templates is still in preview. It works, but the UI might change.
• Processing time - Large ADMX files can take 5-10 minutes to process.

Why ADMX Over Scripts?

I used to run a proactive remediation script for Firefox updates. It worked, but:

• Scripts need maintenance when things change
• More moving parts = more things that can break
• ADMX policies are native and vendor-supported

If the vendor provides ADMX templates, use them. Save scripts for when there’s no other option.

Related Links

• Import custom ADMX templates in Intune
• Firefox enterprise policies
• Zoom ADMX templates