This blog post will be about setting default app associations, or file type associations, on Windows 10 devices. Starting with Windows 10, version 1703, it’s possible to set the default app associations via Windows 10 MDM. In this post I’ll briefly go through this setting and I’ll show how to configure the setting via Microsoft Intune hybrid and Microsoft Intune standalone. I’ll end this post by showing the end-user experience.
Configuration
Starting with Windows 10, version 1703, a new setting was introduced that allows an administrator to set the default file type and protocol associations. When set, default associations will be applied on sign-in to the PC. Every sign-in. In other words, the end-user can make adjustments. However, once the end-user signs-out and signs-in again, the default associations will be applied again. This does require the PC to be Azure AD joined.
Get the required information
Let’s start by getting the required information to configure the custom OMA-URI setting. The required OMA-URI setting is available in the Policy CSP.
OMA-URI setting: ./Vendor/MSFT/Policy/Config/ApplicationDefaults/DefaultAssociationsConfiguration
The required OMA-URI value requires the following steps to get it in the correct format.
| 1 | On Windows 10, version 1703, navigate to Settings > Apps > Default apps and configure the required default apps; |
| 2 | Open Command Prompt and run DISM /Online /Export-DefaultAppAssociations:DefAppAss.xml to export a required app associations file; |
| 3 |
In my example I was only interested in switching to Internet Explorer as the default browser and keeping Microsoft Edge as the default for PDF reading. That allowed me to remove all the remaining content from the DefAppAss.xml. Then I used base64encode.org to easily encode the remaining content of the DefAppAss.xml to Base64 format (see screenshot). |
| 4 | The result in Base64 format is the OMA-URI value. |
Configure the setting
After getting the required information, let’s have a closer look at the configuration of the setting. The setting can be used in Microsoft Intune hybrid and Microsoft Intune standalone, by using the configuration guidelines shown below.
| Environment | Configuration guidelines |
| Microsoft Intune hybrid |
Once the configurations are finished, the created configuration items can be added to a configuration baseline and can be deployed to Windows 10 devices. |
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Microsoft Intune standalone (Azure portal) |
Once the configurations are finished, the profile can be saved and can be deployed to Windows 10 devices. |
Note: This post is based on the custom OMA-URI settings configuration. At some point in time this configuration can come available via the UI of Microsoft Intune standalone and/or hybrid.
End-user experience
Now let’s end this post by having a quick look at the end-user experience. Below on the left is the default Windows configuration and below on the right is the applied policy with the custom app associations. I know that this doesn’t provide a lot of information. However, it does show one important fact, which is that there is nothing preventing the end-user from making adjustments. The end-user can still make adjustments, but those adjustments will be reverted during the next sign-in.
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More information
For more information about the Policy CSP, please refer to this article about the Policy CSP.