For Admins and IT Teams

For organizations that prefer to sideload or manually deploy the current production version of ExtendSync for Outlook, follow the steps below.

📘 READ ME FIRST

Although sideloading is available, we recommend installing the ExtendSync add-in from the Microsoft Office Store or via Centralized Deployment for automatic updates and easier management.

To stay up to date with the latest manifest file and sideload instructions, regularly monitor the Release Notes for any updates or changes.

Installing the Production Add-in

Installing or reinstalling the production add-in involves removing any existing version (such as an older or preview build) and then adding the latest production version using the manifest file URL.

Step 1: Remove the Existing Version

Before installing or redeploying the production version, uninstall any previously installed add-in (e.g., an older build or preview release).

You can always reinstall the latest production version later from the Microsoft Office Store.

Go to https://aka.ms/olksideload, and the Add-Ins for Outlook window will open.
Select My Add-Ins.
Locate the old or preview versions of ExtendSync add-in, click ... in the lower-right corner of the add-in tile, and select Remove.

Microsoft Article: Delete add-in from Outlook

Step 2: Install the Production Version using Manifest File

ExtendSync Outlook Manifest URL: https://manifests.ceol.cloudextend.app/olns-production.xml

Download the file from URL: https://manifests.ceol.cloudextend.app/olns-production.xml
From the Add-ins for Outlook screen, select My Add-Ins.
Scroll down to Add a Custom Add-in → choose Add from File.

Note: The Add from URL option is no longer available to install a custom Outlook add-in. As a workaround, open the URL in your preferred browser to download the add-in file, then use the Add from File option to install it.

A warning prompt will appear. Click Install and wait for the installation to complete.

✅ Congratulations!
You’ve now successfully installed the CloudExtend ExtendSync for Outlook Production Add-in.

Microsoft Article: Install Custom Add-Ins

Removing Older or Test Versions

If your organization previously installed a preview or test version of the add-in, it’s best to remove it to avoid conflicts.

Follow the same steps under Remove the Existing Version, but select the Preview or Test Add-in instead of the production one.

Centralized Deployment

If you plan to deploy ExtendSync organization-wide, consider using Centralized Deployment through the Microsoft 365 Admin Center for automatic updates and easier management.

📘 Learn how to centrally deploy ExtendSync