Enable Automatic Image Downloads in Outlook for Mac Using Your MDM Tool

To make ContactMonkey open tracking work reliably on managed Mac devices, your IT team can deploy the Outlook for Mac preference AutomaticallyDownloadExternalContent through any MDM tool, such as Jamf Pro, Microsoft Intune, Kandji, or Mosyle. This article explains the preference key, its values, and how to deploy and verify it.

ContactMonkey tracks email opens with an invisible tracking pixel. If Outlook for Mac blocks external images, the pixel never loads and opens go unrecorded — so enabling automatic image downloads directly improves the accuracy of your open rates and ensures campaign images display properly.

Prerequisites

• Admin access to your organization's MDM tool
• Mac devices enrolled in your MDM tool
• Outlook for Mac version 16.91 or later on target devices
• Permission from your IT security team — this setting changes how external content loads in emails

What preference controls automatic image downloads in Outlook for Mac?

Outlook for Mac stores this setting in the preference domain com.microsoft.Outlook under the key AutomaticallyDownloadExternalContent. Microsoft documents the following values:

Note: This preference maps to Outlook → Settings → Email → Reading → Download external images in the Outlook for Mac interface. It is CFPreferences-compatible, so any MDM tool that deploys macOS configuration profiles can set it. It does not require a Configuration Profile to take effect, but deploying it as one prevents users from changing it.

For ContactMonkey open tracking, set the value to 2 (all messages) for the most reliable results. Value 1 works only when the sending address is in the recipient's contacts, safe senders, or Global Address List (GAL), which can produce inconsistent open rates.

How do you deploy the preference with your MDM tool?

Use your MDM tool to deploy a configuration profile that targets the com.microsoft.Outlook preference domain. The exact menus differ by MDM tool, but the process follows the same pattern:

1. In your MDM tool, create a new macOS configuration profile and name it descriptively, for example ContactMonkey - Mac Auto-download Images.
2. Add an application preference (often called Application & Custom Settings or Settings catalog) targeting the preference domain com.microsoft.Outlook.
3. Set the key AutomaticallyDownloadExternalContent to integer value 2.
4. Assign the profile to the device group (or groups) containing your managed Mac devices.
5. Save and deploy the profile, then sync a test device to push the policy immediately.

If your MDM tool accepts a raw plist payload instead of a settings catalog, here is an example of what you may use (feel free to revise as needed):

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>AutomaticallyDownloadExternalContent</key>
    <integer>2</integer>
</dict>
</plist>

If you use Microsoft Intune, follow the step-by-step guide in Enable Automatic Image Downloads for Mac Devices in Microsoft Intune instead — it walks through the Intune settings catalog directly.

How do you verify the setting on a Mac device?

1. On a managed Mac, open Outlook and go to Settings → Email → Reading.
2. Confirm Download external images is set to download in all messages. If the option appears greyed out, your MDM profile is enforcing it correctly.
3. Send a test campaign from ContactMonkey to the device and confirm images load without a download prompt, then check that the open registers in your campaign report.

Troubleshooting

Problem: The preference is deployed, but Outlook still blocks images.
Solution: Quit Outlook fully and reopen it — the setting only applies when Outlook restarts. Confirm the profile targeted the user context (not only the root account) and that the device has synced with your MDM tool.

Problem: Opens register inconsistently across recipients.
Solution: Check whether the value was set to 1 instead of 2. With value 1, images load only when the sender is in the recipient's contacts, safe senders, or GAL. Set the value to 2 for consistent tracking.