Install the Bybrand Outlook Add-in (Organization-wide deployment)

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This tutorial explains how an administrator can deploy the Bybrand Outlook add-in across the entire organization (or to specific groups) using the Microsoft 365 admin center. The process is straightforward and only takes a few minutes.

Video tutorial:

Before you begin

Make sure you have the Bybrand manifest.xml file saved on your computer. If you don’t have it yet, you can download it from the Integrations section of your Bybrand account.

You will also need:

• A Global administrator account (or equivalent permissions to deploy add-ins).
• Access to the Microsoft 365 admin center.

Step 1: Access the integrated apps section

• Sign in to the Microsoft 365 admin center using your administrator account.
• In the left menu, click Show all (if necessary).
• Click Settings and then select Integrated apps.
• Click Upload custom apps.

Step 2: Upload the manifest.xml and validate

In this step, you will upload the manifest.xml file from your computer.

1. Upload the manifest.xml file.
2. Click Validate (or proceed until automatic validation completes).

Next, choose whether you want to deploy the Bybrand add-in to:

• Entire organization, or
• Specific users/groups.

To complete the process:

1. Accept the required permissions.
2. Finish the deployment.
3. Click Next to start the deployment process.

After that, the add-in will appear in Integrated apps, and you can later edit access if needed.

Step 5: Verify the deployment

The deployment may take up to 72 hours to become visible to 100% of users, depending on Microsoft 365 propagation.

If a user does not see the Bybrand add-in:

• Ask them to refresh Outlook (reload the page in Outlook Web), or
• Close and reopen Outlook (Desktop).

This usually forces the update and helps the add-in appear faster.

What end users should see

Outlook on the Web (OWA)

The add-in appears when composing a new email, typically under Apps / Add-ins in the message window.

Outlook Desktop

It may take slightly longer to propagate due to local policies and client-side cache.

See full details here:

• How the Outlook Add-in works

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Tips and common troubleshooting

I deployed it, but the user doesn’t see the add-in

• Confirm the user is included in the selected scope (Entire organization or Specific users/groups).
• Go back to Integrated apps, select the Bybrand add-in, and review user access.
• Ask the user to close and reopen Outlook/OWA (cache and session often affect visibility).

Manifest validation failed

This typically indicates an issue with the manifest itself (inaccessible URLs, formatting issues, or unmet requirements).

Microsoft recommends deploying through the Integrated apps portal, as it provides the most complete validation process.

I want to change from group deployment to the entire organization

You can edit the deployment scope later:

• Go to Integrated apps, select the Bybrand add-in, and update access settings.

The signature is not loading for the user

Make sure employees have the correct signature configured in Bybrand.
The add-in can only load a signature if it is properly assigned to the employee.

• See: How linked signatures work.

The Bybrand add-in for Outlook is not working correctly

For the Bybrand add-in for Outlook to function correctly, third-party cookies must be enabled in the user’s browser.

How to do it:

1. Open their browser settings.
2. Go to Privacy and Security → Cookies and other site data.
3. Make sure third-party cookies are allowed

After enabling third-party cookies:

• Refresh Outlook on the Web, or
• Close and reopen the browser.

It appears in Outlook Web but not in Outlook Classic (Windows)

A common cause is Outlook/Office cache preventing the add-in from updating properly. Clear the Office/Outlook add-in cache to resolve issues related to outdated content.

After clearing the cache, completely close Outlook and reopen it.