Microsoft introduced the “Try the new Outlook” toggle in the classic Outlook desktop app. This toggle switches your profile from the classic ribbon-based interface to the new Outlook for Windows experience. The new Outlook is a web-based app that replaces the traditional Win32 client. It offers a modern interface, tighter Microsoft 365 integration, and access to features like Microsoft Copilot and Loop components. This article explains what the new Outlook toggle does, how to use it, and what classic Outlook users should know before switching.
Key Takeaways: New Outlook Toggle for Classic Users
- Toggle location in classic Outlook: The “Try the new Outlook” switch appears at the top-right corner of the classic Outlook window, next to the minimize button
- What happens when you toggle: Your profile, mail, calendar, contacts, and rules are synced automatically to the new Outlook without data loss or reconfiguration
- How to revert: Open the new Outlook, go to Help > About, and click the “Try the classic Outlook” toggle to switch back instantly
What the New Outlook Toggle Does
The new Outlook toggle is a one-click switch that converts your classic Outlook profile into the new Outlook for Windows. The new Outlook is a Progressive Web App (PWA) that runs on a Microsoft Edge WebView2 engine. It is designed to replace the classic Win32 client over time. When you toggle on, classic Outlook closes, and the new Outlook opens with your existing account data, folders, and settings already loaded.
The toggle is available in Outlook 365, Outlook 2021, and Outlook 2019. It is not available in Outlook 2016 or earlier versions. Microsoft plans to make the new Outlook the default experience for all Microsoft 365 users starting in 2024.
What Gets Transferred
When you toggle to the new Outlook, the following items are synced from your classic profile:
- Email accounts and their server settings
- Mail folders and their contents
- Calendar events and appointments
- Contacts and contact groups
- Rules and quick steps
- Signatures and automatic replies
Items that do not transfer include local PST files, custom views, COM add-ins, and VBA macros. These remain in the classic Outlook profile and are not accessible in the new Outlook.
How to Use the New Outlook Toggle
The toggle is a simple on-off switch. Follow these steps to switch from classic Outlook to the new Outlook:
- Open classic Outlook
Launch Outlook 365, Outlook 2021, or Outlook 2019 on Windows 10 or Windows 11. - Locate the toggle
Look at the top-right corner of the Outlook window, directly to the left of the minimize button. You will see a switch labeled “Try the new Outlook.” The switch is gray when off and blue when on. - Click the toggle to turn it on
Click the switch. A dialog box appears asking you to confirm the switch. Click the “Try the new Outlook” button in the dialog. Classic Outlook closes automatically. - Wait for the new Outlook to load
The new Outlook for Windows opens. Your accounts and data sync within a few seconds. You may see a loading screen while the sync completes.
To switch back to classic Outlook, open the new Outlook, click Help at the top of the window, select About, and then click the “Try the classic Outlook” toggle. Classic Outlook reopens with your original profile intact.
Common Issues and Limitations When Switching
Missing Add-ins and Macros After Switching
The new Outlook does not support COM add-ins, VBA macros, or third-party plugins. If you rely on add-ins for CRM, email tracking, or automation, those features will stop working. To use those add-ins, stay on classic Outlook. Microsoft plans to add add-in support in future updates, but no timeline is confirmed.
Local PST Files Are Not Accessible
If you use PST files for archiving or storing data locally, the new Outlook cannot open them. PST files only work in classic Outlook. To access archived email, open classic Outlook and export the PST contents to an online mailbox before switching.
Shared Mailbox and Calendar Permissions
Shared mailboxes and calendars that you have permissions to open in classic Outlook should appear automatically in the new Outlook. However, if the shared resource uses a custom permission set or is stored on an on-premises Exchange server, it may not sync. Contact your IT administrator to verify that your mailbox is hosted on Exchange Online.
Search Results Differ Between Versions
The new Outlook uses a different search index than classic Outlook. Search results in the new Outlook may not include items stored in offline OST files or PST archives. If search is critical to your workflow, test the new Outlook with a few searches before switching permanently.
New Outlook vs Classic Outlook: Key Differences
| Item | New Outlook | Classic Outlook |
|---|---|---|
| Application type | Progressive Web App (PWA) on WebView2 | Win32 desktop application |
| Add-in support | Web add-ins only | COM add-ins and VBA macros |
| Offline access | Limited offline mode with cached data | Full offline mode with OST file |
| PST file support | No | Yes |
| Microsoft 365 integration | Copilot, Loop, Microsoft Forms, Bookings | Limited to classic add-ins |
| Custom views | Not supported | Supported |
| Rules and Quick Steps | Basic rules only, no Quick Steps | Full rules and Quick Steps |
The new Outlook is designed for users who rely on Microsoft 365 cloud services and do not need legacy features like PST files or COM add-ins. Classic Outlook remains available for users who require offline archive access, custom views, or third-party automation tools.
You can now switch between the new Outlook and classic Outlook using the toggle. Before switching, verify that your add-ins and PST files are not critical to your daily work. If you need to use classic Outlook features, keep the toggle off. Microsoft recommends testing the new Outlook in a non-production account first to identify any missing functionality.