Teams Classic Client Slipping Away

Final Retirement of the Teams Classic Client in July 2025

The current Teams classic client is the last iteration of the original client launched in preview in November 2016 as a “chat-based workspace” (Figure 1) Teams reached general availability in February 2017 and remained the focus for customers until the arrival of the preview of the Teams 2.1 client (code name “Emblem”) in March 2023.

Why version 2.1 instead of Teams 2.0? Well, the Teams 2.0 client was the first run at a new architecture that appeared as the chat client in Windows 11. That client lacked any of the enterprise features that Teams built its 320 million installed base on, and really wasn’t very good. That problem is addressed in the single desktop application “unified Teams client” (Microsoft 365 roadmap 383006), which is now rolling out.

Many Changes Since 2016

The elements of the original Teams client from 2016 are recognizable when compared to the final release of the V1.0 client but so much changed over the seven years of active development. The most notable

• Worldwide deployment to support customer data residency needs.
• Scalability improvements from the original 600-member limit for a team to 10.000.
• Support for compliance functionality like retention, data loss prevention, and communications compliance policies.
• Massive change and increased functionality in calling, meetings, and webinars, including the migration from Skype for Business Online and the introduction of the Teams Phone ecosystem.
• Shared and private channels, and up to 1,000 channels per team.
• Support for automation through PowerShell module and Graph APIs.
• Development of the Teams app ecosystem, including app setup and permissions policies and bulk deployment.

All the above happened using the original Electron-based client. Soon after its release, Teams took over from Outlook as the favorite example of a piggy application when it came to the consumption of workstation resources. Increased functionality extracts its price, but Electron added more on top.

Teams Classic Client Retirement Schedule

Which brings us to message center notification MC783985 (23 April 2024), which lays out the retirement schedule for the classic Teams client.

On July 1, 2024, the Teams classic client exits support. Users will see nagging messages to remind them that support is no longer available. This “helpful” communication has already started (Figure 2) to join the other annoying messages surfacing in Teams.

Starting on October 23, 2024, Microsoft will block use of the classic client on older platforms such as Windows 7 (still heavily used by large organizations), Windows 8 and 8.1 (ignored by most), and macOS Sierra (10.2). Users of these platforms can switch to the new Teams browser client, but can’t use the new client because of the requirement to use Windows 10 version 10.0.19041 or higher or macOS Monterey (12) or higher.

On July 1, 2025, the Teams classic client reaches “end of availability” and is blocked. Users who attempt to use the classic client see a non-dismissible dialog telling them that they must upgrade. Those using supported platforms can choose between the new client desktop or browser versions. It’s worth noting that Microsoft now supports the new client with the Firefox browser for Windows, macOS, and Linux and the Safari browser for macOS. Previously, the new client only supported Chrome and Edge.

Smooth Transition to Teams 2.1

I haven’t heard of many issues as organizations make the transition to the new Teams client. The new client is faster, consumes fewer resources, and boasts a wonderful account switching capability that makes it much easier to move between tenants. You can even run the new client with a classic skin to make it look like the old client.

Some issues remain for Microsoft to resolve, but that’s always the case in software transitions. Balancing the lack of some features that exist in the old client and are not yet in the new are the introduction of new functionality like enhanced noise suppression during meetings (MC780744) and intelligent message translation for chats (MC748379). A trnslation capability for Teams channel conversations and chats has existed since 2018, so I’m not quite sure what the “intelligent translation” means, especially when translation doesn’t work sometimes. Figure 4 shows the same message sent twice to a group chat. One translated, one didn’t.

I guess the intelligence comes from the way that translation happens automatically if you configure this in Teams Settings. And to be fair, it does work – most of the time. The joys of software…

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