Classic Outlook v’s New Outlook

Why You Might Want to Wait Before Switching
Note: This blog post refers to Classic Outlook as the traditional M365 Outlook for Windows Desktop Client that has been a staple in business environments for many years
You may already be using the New Outlook or perhaps you have seen the ‘Try the new Outlook’ switch appearing in your Outlook Client. What is clear is that it will eventually replace the Classic Outlook, but the transition will be gradual. Microsoft plans to support the Classic Outlook for Windows until at least 2029.

What is the New Outlook (Project Monarch)?
The New Outlook, previously known by the codename Project Monarch, aims to provide a unified experience across platforms (Windows, Mac, and web). It features a modern web user interface, improved performance, and better integration with M365 technologies like Teams, OneDrive, SharePoint, Power Automate, and Copilot.
This is not just an update to an existing product like we are used to when moving from Outlook 2016 to 2019 to 365, etc. This is a complete rebuild of the product on new technologies.
The big win for Microsoft here is that the different versions across all platforms (Windows, Mac) will be built upon a common codebase and design, making them much easier to manage and update. The big win for us users is that we will have a similar user experience across all our devices.

Why Might You Hold Off Switching?
Well, a lot of us don’t like change, and in this case, with valid reason! Many key features from Classic Outlook are still missing in the New Outlook or are not quite the same as they were. This will change with updates, so keep an eye on this Microsoft comparison page.
However, two of the biggest issues are the lack of support for COM Add-ins and VBA scripting. These issues will never be fully resolved.
COM Add-ins: Classic Outlook supports COM add-ins for extensive customisation and integration with other software. This technology is incompatible with the New Outlook. Instead, the New Outlook uses Office web add-ins based on HTML and JavaScript. This means that some companies will likely release new versions of their add-ins over time, but many will not, particularly in the case of legacy systems.
VBA Scripting: VBA (Visual Basic for Application.) in Classic Outlook allows for task automation and is the gateway that allows integration with other custom-built Microsoft Office solutions. This technology is incompatible with the New Outlook. Instead, it seems the preferred method of automation going forward will be to use Power Automate. Many businesses rely on custom VBA tools built in the likes of Excel or Access that interact with Outlook, for generating automated emails, sending bulk mail merges, monitoring inboxes for certain mail items, and automatically setting up calendar events.
Conclusion
While the New Outlook offers new features and improvements, the loss of COM add-ins and VBA will be significant drawbacks for many. This will likely lead to many organisations sticking with Classic Outlook or rolling back in order to maintain their existing workflows and custom solutions.
On a side note, hopefully, they come up with a better name than New Outlook soon!
Olas's Application Development Team
Our Application Development team specialises in finding custom solutions for our clients. Over the years, we have both created and supported many Microsoft Office solutions that rely heavily on VBA or COM add-ins for Outlook. Going forward, we will continue to find new solutions to adapt to the challenges posed by changing technologies and to inform our clients of the implications of these changes.
