How to install an Outlook add-in to view the Microsoft 365 End-User Quarantine

This article explains how to install an Outlook add-in that will open the Microsoft 365 end-user quarantine in a browser with a single click. This makes it really easy to access the quarantine directly from Outlook. And since this is a true Office add-in, it also displays and works in Outlook mobile and Outlook on the web!

View the add-in change log for status and feature updates.

The add-in displays in the Outlook ribbon when viewing any folder that contains mail items.

The View Quarantine add-in for Outlook

The Microsoft 365 end-user quarantine

I originally built this add-in using the Build your first Outlook add-in - Office Add-ins documentation. This gave me a good head start to build and customize the add-in.

The View Quarantine add-in source files are available for free on my website here. The add-in consists of three files plus icons in various sizes for the different platforms.

Source File	Description
commands.html	An HTML "wrapper" that calls the JavaScript used by the add-in when the button is clicked.
commands.js	The JavaScript functions that provide status and opens the end-user quarantine in a browser.
manifest.xml	The real heart of the add-in. It defines the unique ID for the add-in and describes when to display the View Quarantine button and how the add-in functions.
assets folder	Contains six icon files of different sizes and opacity for Outlook, OWA, and Outlook mobile.

I'm currently in the process of publishing this add-in to the AppSource marketplace via the Microsoft Partner Center, which may take a week or so to certify. In the meantime, there are two ways you can try out the View Quarantine add-in now.

Option 1 -- Install via the Web

You can install the add-in from my website until Microsoft publishes it on AppSource.

Open Outlook and click the Get-Add-ins button in the ribbon.
Click My add-ins in the top left.
Click the + Add a custom add-in dropdown at the bottom of the window under Custom add-ins, then select Add from URL...
Enter the following URL: https://www.expta.com/quarantine/manifest.xml and click OK.

You will see a warning before installation. Click Install to install the add-in.

The add-in will now be listed under Custom add-ins. Note: To remove the View Quarantine add-in at any time, click the ellipses (...) and select Remove.

Close the Add-ins window to add it to the Outlook ribbon.

Option 2 -- Install from Source Files

You can also install the add-in using the manifest.xml file in my source files.

Download the View Quarantine source files from my website.
Extract the ZIP file to a local drive or network share.

Open Outlook and click the Get-Add-ins button in the ribbon (shown above).
Click My add-ins in the top left.
Click the + Add a custom add-in dropdown at the bottom of the window under Custom add-ins, then select Add from file...
Browse to the manifest.xml file and click Open.
You will see a warning before installation. Click Install to install the add-in.

The add-in will now be listed under Custom add-ins.

Close the Add-ins window to add it to the Outlook ribbon.

Deploying to All Users in the Organization

Once you're satisfied that the add-in is installed and working properly, you can deploy it to all users in your organization. Here's how to do that:

Open the Exchange Admin Center and navigate to Organization > add-ins.
Install the manifest file by clicking the + drop down button and do one of the following:

To install from the web, select Add from URL, enter https://www.expta.com/quarantine/manifest.xml, and click OK
To install from the source files, select Add from File, browse to the manifest.xml file you downloaded above, and click OK