Install Secure Exchanges on Outlook Web

How do I install and activate Secure Exchanges on Outlook Web?

This article explains how to install the Secure Exchanges add-in in Outlook Web (outlook.office.com) and Outlook New (the new version of the Windows client).

Warning
This procedure does not apply to Outlook Classic (the old desktop client). If you want to install Secure Exchanges on Outlook Classic, follow this procedure instead: How do I install and activate Secure Exchanges for Outlook?

Notes
📋 In short
  1. Who is it for? Outlook Web or Outlook New users with a Microsoft 365 work or school account.
  2. What you need: an active M365 account, connected to Exchange Online, on a plan that allows add-ons.
  3. 3 possible paths depending on your role: administrator (A), authorized user (B), unauthorized user (C).
  4. Duration: approximately 10 to 15 minutes. The module may take up to 24 hours to appear after deployment.
What procedure should you follow? (determine your situation)

The installation depends on your role in Microsoft 365 and your account permissions. Answer the two questions below, in order, to identify your situation.

Question 1 — Do you manage your organization's Microsoft 365 account?

In practical terms: you are the one who adds or removes users, manages licenses and receives invoices from Microsoft.

  • Yes → you are in Situation A. Proceed directly to Procedure 1 .
  • No, or I don't know → go to Question 2 .

Question 2 — Can you install an add-on yourself? (visual test)

  1. Open Outlook Web or Outlook New .
  2. Click on New message .
  3. Click on the Applications icon (dot grid).
  4. Click on Get add -ins.
  5. In the left panel, click on My Add-ins.
  6. Scroll to the bottom of the page, to the Custom Addins section.
  7. What do you see?
    • The + Add a custom add-in button is present → you are in Situation B. Follow Procedure 2 .
    • The section is missing, greyed out or displays an error → you are in Situation C.

Info
Choose your procedure below.
Procedure 1 — Deployment by the Microsoft 365 administrator
Procedure 2 — User Installation
Procedure 1 — Deployment by the Microsoft 365 administrator

Follow this procedure to deploy Secure Exchanges to all (or a targeted group) of your users.

Next steps:

  1. Open a browser and access the Microsoft 365 Admin Center : https://admin.cloud.microsoft/?#/Settings/IntegratedApps
  2. Log in with your administrator credentials.
  3. Click on " Load custom applications"

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  4. Select " Office Add-in" .

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  5. In the " Provide a link to the manifest" field, paste the following URL: https://office365.secure-exchanges.com/SecureExchanges.xml and then validate.

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  6. Click "Next" and choose who to deploy Secure Exchanges to.

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  7. Click "Next" and then "Accept Permissions" to accept the permissions requested by Secure Exchanges.

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  8. Click on " Complete deployment ."

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Info Info — Appearance time — The module may take up to 24 hours to appear in Outlook after deployment.

Notes Once the module is installed, you must activate your license to use it. See the article below.
Procedure 2 — User Installation
Follow this procedure to install Secure Exchanges on your own account. It requires that your account allows the installation of custom add-ons ( Situation B above).

Next steps:

  1. In your browser, go to the following address: https://office365.secure-exchanges.com/SecureExchanges.xml

  2. Right-click on the page, then select " Save As" to download the SecureExchanges.xml file to your computer.

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  3. Open Outlook Web or Outlook New .
  4. Click on " New message" to open the email composition window.
  5. In the editing window, click on the " Applications" icon (dot grid).

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  6. Click on " Get add-ins" .

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  7. In the left panel, click on " My Add-ins" , scroll down to the " Custom Addins" section, and then click on " + Add a custom add-in" .

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  8. Choose " Add from File" , then select the SecureExchanges.xml file downloaded in step 1.

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  9. Confirm the installation when the system prompts you to do so.

Notes Once the module is installed, you must activate your license to use it. See the article below.

Steps to follow to activate your license

  1. Sign in to Outlook Web or Outlook New.
  2. Click on New message.
  3. In the message toolbar, click the Applications icon (dot grid).

  1. In the list of applications, click on Secure Exchanges .
  1. Click on "Activate my license"


🎉 Your license is now activated. You can send your first secure email. See: Send a secure message with Secure Exchanges Outlook Web for instructions.

Troubleshooting

The Secure Exchanges module does not appear after deployment

Possible causes : The 24-hour period has not yet expired, or your account is not included in the deployment group. Solution : Wait 24 hours. If the module still does not appear, contact your administrator to verify the composition of the deployment group.

The "Load custom apps" button is missing

Cause : Your administrator privileges are insufficient to manage the integrated applications. Solution : Contact your organization's primary administrator, if your account allows it.

The module is visible to only certain users

Cause : The deployment was limited to a specific group. Solution : The administrator must verify the composition of the deployment group in the Microsoft 365 admin center.

The "Custom Addins" section is missing or "+ Add a custom add-in" is greyed out.

Possible causes :

  1. Your Microsoft 365 plan does not support add-ons (Business Basic, Exchange Online only, personal account, etc.).
  2. Your Microsoft 365 administrator has disabled user module installation.

Solution : Ask your Microsoft 365 administrator to deploy Secure Exchanges via Procedure 1.

See also