3/26/24 Editor's note - This article has been updated to show the link to the newest update to the harmon.ie add-in
We have long heard from Outlook users and organization IT admins that the fragmented experience of Outlook across platforms is painful and frustrating. With the new Outlook for Windows, we are bringing a more consistent and robust experience with rapid access to new features, so our users are empowered to use Outlook the way they like, with the best tools at their fingertips. Part of this effort is making sure that the add-ins platform and deployment experience is consistent across Outlook endpoints, and that add-ins are supported reliably for end users.
In the new Outlook for Windows, web add-ins are fully supported, with no additional work required from partners. COM Add-ins will not be supported in the new Outlook for Windows but will continue to work in classic Outlook for Windows. COM add-ins could manipulate Outlook in many ways but that often led to instability and crashes in Outlook. Web add-ins provide a sandboxed environment for add-ins to operate in and have checks and balances in place to ensure Outlook is more stable and robust.
Some of the differences that you find in COM vs web add-ins, for example fixed entry points, are intended to provide a more consistently stable experience for all Outlook users.
Note that classic Outlook supports web add-ins and will continue to get the latest web add-in features. For web add-ins in both new Outlook and classic Outlook for Windows, we are enriching the web add-ins platform with modern capabilities and richer integrations such as running add-ins automatically on event changes without disrupting users, allowing users to run add-ins on multiple items, running validations and remediations on items at send, enhancing phish reporting providing contextual mail tips, updating mail or event details, and much more.
Transitioning Add-ins from classic Outlook to the new Outlook for Windows
If your organization is currently using web add-ins, no additional effort is required to use it in the new Outlook. If your organization is using a COM add-in, there are a few steps you can take to transition to web add-ins:
- Check your installed COM add-ins: You can check installed COM/VSTO add-ins from the Microsoft 365 Apps health dashboard in the Microsoft 365 Apps admin center. Follow the instructions here to find your installed apps – make sure to filter out only the Outlook add-ins.
- Identify the mission-critical COM add-ins from this list: Often, organizations have unused COM add-ins installed that are no longer relevant. It is important to identify which of the installed COM add-ins are used by your organization and prioritize those to prepare your organization for the new Outlook for Windows. You may need to work with your relevant business groups or IT teams to identify the relevant COM add-ins.
You may find some Microsoft COM Add-ins deployed for your organization. The plan for these is detailed below –
Microsoft COM Add-in
Details
Dynamics 365
COM Add-in deprecated in favor of web add-in since 2020.
Microsoft Azure Information Protection (AIP)
This is being replaced with native Office integration for sensitivity labels. You can find more details here.
Microsoft Exchange Add-in
This add-in is no longer relevant.
Microsoft IME (Input Method Editor)
Outlook アドイン
Microsoft IME can be enabled in Windows and that should solve the relevant scenarios.
Microsoft SharePoint Server Colleague Import Add-in
No web add-in equivalent will be available for this add-in. However, this is not actively used by most organizations.
OneNote COM Add-in
Share to OneNote web add-in is available for use. There are some known gaps that the OneNote team is looking into and plans to address.
Teams COM Add-in
Native integration in the new Outlook for creating Teams meetings. Share to Teams web add-in is also available.
- Check if web add-ins are available for use: If a web add-in is available for use, please install, test, and assess it for usage with the new Outlook for Windows. You can follow the steps here to install a web add-in: Deploy Add-ins in the Admin Center.
- Some widely used COM add-in publishers have also published their web add-ins as below. The ones marked ‘PRIVATE’ do not have a web add-in published to the store but have a private web add-in; you can reach out to the partners for requesting access to it.
COM Add-in
Scenario
Web add-in
Adobe Acrobat Sign
Signature Management
Barracuda Archive Search for Outlook
Attachment Management
Blue jeans Outlook Add-in
Online Meetings
Calendly for Outlook
Meeting Boosters
Cisco Webex Meetings
Online Meetings
Citrix Files for Outlook
Attachment Management
Cofense Reporter
Phishing/Spam Reporting
PRIVATE- Cofense
Egress
Encryption & Classification
Evernote.Outlook
Productivity
Google Meet Outlook Add-in
Online Meetings
GoToMeeting Outlook COM Add-in
Online Meetings
harmon.ie
Attachment Management
Jira
Project Management
Mimecast for Outlook
Phishing/Spam Reporting
OnePlaceMail
Attachment Management
KnowBe4 PhishAlarm Outlook Add-In
Phishing/Spam Reporting
PRIVATE-KnowBe4
Proofpoint Outlook Plug-in
Phishing/Spam Reporting
PRIVATE-Proofpoint
Proofpoint Plug-in
Phishing/Spam Reporting
PRIVATE-Proofpoint
RingCentral Meetings Outlook Plugin
Online Meetings
Salesforce for Outlook
CRM
Symantec Endpoint Protection Outlook Add in
DLP
PRIVATE-Symantec
Vera AddIn for Outlook
DLP
Private Vera
Virtru For Outlook
DLP
PRIVATE-Virtru
Zoom Outlook Plugin
Online Meetings
- If you don’t find your relevant COM add-ins in this list, please search for them in the Microsoft AppSource store.
- Some developers build private web add-ins that are not published to the store. Please check with your partners to confirm if they have developed or are developing a web add-in.
- Some widely used COM add-in publishers have also published their web add-ins as below. The ones marked ‘PRIVATE’ do not have a web add-in published to the store but have a private web add-in; you can reach out to the partners for requesting access to it.
- Explore native Outlook capabilities: If you find that your mission critical COM add-ins do not have an equivalent web add-in, you can explore new Outlook’s native capabilities and see if they work for your scenario. Some examples include:
COM Add-in
Native Outlook capability
Online Meeting
Teams meetings in Outlook
Security : DLP, Phishing & Spam
Microsoft Information Protection (sensitivity labels, permissions) and Report Message
Email proofing
Microsoft Editor
Signature
Outlook Signatures
- Initiate Web add-in development: If native Outlook capabilities do not meet your needs, please reach out to your partners or internal developer teams (in case of internally developed COM add-ins) to initiate web add-in development. These are some resources you can share with your partners or developers to start building web add-ins.
- Develop Outlook add-ins for the new Outlook for Windows: this document has details on the supported and unsupported COM add-in scenarios in the web add-ins platform.
- Build your first Outlook add-in - Office Add-ins | Microsoft Learn
- Tutorial: Build a message compose Outlook add-in - Office Add-ins | Microsoft Learn
- Outlook add-in APIs
- Note that in addition to the JS APIs supported by the web add-in platform, developers can also use Graph API integrations to augment the add-in capabilities.
Request improvements in the web add-in platform
Our goal is to provide support for core scenarios through a combination of add-in JS and Graph APIs. Many scenarios, such as launching an add-in automatically on mail send or an event change, multi-selecting items for the add-in to run on, and updating mail or writing to the add-in product’s server are supported. For a full list of scenarios, check our guide for developing add-ins for new Outlook: Develop Outlook add-ins for the new Outlook on Windows (preview) - Office Add-ins | Microsoft Learn.
If you find that there are gaps in the web add-in platform that do not support core workflows like the COM add-in, please use this form to share feedback.
Please leave your thoughts and comments below!
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