Outlook Mobile External Image Blocking: How to Configure Per Account

Outlook Mobile for iOS and Android blocks external images by default to protect your privacy and security. When a sender includes an image hosted on a remote server, Outlook does not download it automatically. This prevents senders from tracking whether you opened their email. This article explains the feature, how to enable or disable image blocking per account, and what to expect when images are blocked.

How External Image Blocking Works in Outlook Mobile

External images are pictures stored on a remote server, not attached to the email. When you open a message, the email client must send a request to that server to download the image. This request includes your IP address and confirms that you opened the email. Marketers and malicious actors use this technique to track opens, learn your location, and verify your email address is active.

Outlook Mobile blocks these automatic requests. Instead of downloading the image, it shows a placeholder. You can choose to download images for a single message or change the default behavior for an entire account. The setting is available for each account you add to the app, including Outlook.com, Exchange, Gmail, Yahoo, and iCloud.

Prerequisites

You need Outlook Mobile version 4.0 or later installed on iOS 14 or Android 8. The per-account image blocking setting is available for all account types supported by Outlook Mobile. No administrator policy is required for personal accounts. For work or school accounts, your IT administrator may enforce a global policy that overrides the per-account setting.

Steps to Configure External Image Blocking Per Account

Follow these steps to enable or disable external image blocking for a specific account in Outlook Mobile.

1. Open Outlook Mobile and go to Settings
   Tap your profile picture or initials at the top left of the screen. Then tap the gear icon in the bottom left corner to open Settings.
2. Select the account you want to configure
   Under the Accounts section, tap the name of the email account. This opens the account settings screen.
3. Tap Email Security
   Scroll down and tap the option labeled Email Security. This menu contains privacy-related settings for the selected account.
4. Toggle Block External Images
   Find the switch labeled Block External Images. To block images, move the switch to the on position. To allow automatic downloads, move it to the off position. The change takes effect immediately for new messages you open.
5. Repeat for other accounts
   Go back to the Settings screen and repeat steps 2 through 4 for each account you want to adjust. Each account has its own independent setting.

What Happens When Images Are Blocked

When Block External Images is on, Outlook Mobile does not download remote images automatically. In the message body, you see a gray placeholder box with a camera icon and the text This external image has been blocked. Tap the placeholder to download and display that single image. You can also tap the banner at the top of the message that says Blocked external images to load all blocked images in that message.

Images that are attached directly to the email or embedded as inline attachments are not affected. Only images hosted on external servers are blocked. The setting does not affect images from trusted senders or domains unless your IT administrator has configured additional policies.

If the Setting Does Not Take Effect

Outlook Mobile Still Shows Images After I Turned Blocking On

First, confirm you changed the setting for the correct account. Open Settings > Accounts > Account Name > Email Security and verify the switch is on. If the switch is on but images still load automatically, close Outlook Mobile completely and reopen it. On iOS, swipe the app up from the app switcher. On Android, go to Settings > Apps > Outlook > Force Stop. Then relaunch the app.

I Cannot Find the Email Security Option

The Email Security option appears only for accounts that support external image blocking. If you are using an older version of Outlook Mobile, update the app from the App Store or Google Play Store. For work or school accounts, your IT administrator may have removed this option by policy. Contact your help desk for assistance.

Images from Specific Senders Still Load

Outlook Mobile does not have a per-sender exception list for image blocking. If images from a particular sender always load, verify that the sender is not in your contacts or safe sender list. Outlook Mobile may automatically trust senders in your contacts list. Remove the sender from your contacts or safe sender list to enforce the block.

Image Blocking Behavior: Outlook Mobile vs Outlook Desktop

Item	Outlook Mobile	Outlook Desktop
Setting location	Settings > Accounts > Account Name > Email Security	File > Options > Trust Center > Trust Center Settings > Automatic Download
Per-account control	Yes, each account has its own toggle	No, the setting applies globally to all accounts in the profile
Blocked image placeholder	Gray box with camera icon	Red X in a box
Option to load images per message	Tap the placeholder or banner	Click the InfoBar at the top of the message
Override by IT policy	Possible for work or school accounts	Possible for work or school accounts

The key difference is that Outlook Mobile allows per-account configuration, while Outlook Desktop applies the same setting to all accounts in the profile. If you use both apps, configure each one separately.

Now you can control external image blocking independently for each account in Outlook Mobile. To further reduce tracking, enable the Block read receipts setting in the same Email Security menu. For advanced protection, consider using the Outlook Mobile built-in phishing filter, which warns you about suspicious links in messages.