Microsoft has resolved a frustrating issue that caused the classic version of Outlook to repeatedly crash for users who had the Microsoft Teams Meeting Add-in enabled. The problem, first reported on March 12, left many users unable to access their email without Outlook prompting them to start in Safe Mode – a diagnostic mode that limits functionality.
The disruption stemmed from a compatibility conflict between older builds of Outlook and the latest version of the Teams Meeting Add-in. For many, the issue manifested as a complete inability to open Outlook, halting email communication and impacting daily workflows. The fix, rolled out with the latest Microsoft Teams update, aims to restore stability for those affected.
What Caused the Outlook Crashes?
Microsoft acknowledged the problem nearly a week after initial reports surfaced, issuing a Microsoft 365 incident report (EX1254044) that pinpointed the source of the crashes. According to a support document, the issue arose when older versions of Outlook attempted to run version 1.26.02603 of the Teams Meeting Add-in. Specifically, the crashes occurred on the Current Channel if the Outlook build was Version 2402 (Build 17328.20142) or lower.
The Teams Meeting Add-in is designed to streamline the process of scheduling and joining Teams meetings directly from within Outlook. However, this latest incident highlights the challenges of maintaining compatibility across different versions of Microsoft’s interconnected software suite.
How to Resolve the Issue
Microsoft announced the resolution on Monday, stating that a fix was included in Microsoft Teams version 26058.712.4527.9297. The company advises users experiencing crashes to update their Outlook client to the latest build. For those unable to immediately update, Microsoft recommends performing an Online Repair, which reinstalls all Office applications.
As a temporary workaround, users can disable the problematic Teams Meeting Add-in. To do so, Outlook must be opened in Safe Mode (by holding down the Ctrl key while starting the application, or following the steps outlined here). Once in Safe Mode, users can navigate to File > Options > Add-ins > Proceed, uncheck “Microsoft Teams Meeting Add-in for Microsoft Office,” and restart Outlook.
Part of a Pattern of Outlook Instability
This isn’t an isolated incident. Microsoft has been actively addressing a series of bugs affecting the classic Outlook client in recent months. Last week, the company resolved a separate issue that was causing synchronization errors for Gmail and Yahoo accounts, triggering 0x800CCC0F and 0x80070057 errors, which began in February. Earlier this year, a bug stemming from December 2025 updates prevented some Microsoft 365 customers from opening encrypted emails.
Currently, Microsoft is also investigating a bug that causes “Can’t connect to the server” errors when creating groups in classic Outlook when Exchange Web Services (EWS) is enabled. Another acknowledged issue, reported nearly two months ago, causes the mouse pointer to disappear for some users in Outlook, OneNote, and other Microsoft 365 applications.
What So for Outlook Users
These recurring issues underscore the complexities of maintaining a legacy application like classic Outlook while simultaneously integrating it with newer services like Microsoft Teams. While Microsoft continues to invest in the “New Outlook” experience, many users still rely on the classic version for its established features and workflow. The recent spate of bugs highlights the need for rigorous testing and quality assurance as Microsoft continues to update and integrate its suite of productivity tools.
For users, the immediate takeaway is to ensure both Outlook and Teams are updated to the latest versions. Regularly checking for updates and being aware of potential workarounds, like disabling the Teams Add-in, can minimize disruption. Microsoft’s support website remains the best resource for official updates and troubleshooting guidance.
Microsoft has not provided a specific timeline for addressing the “Can’t connect to the server” and disappearing mouse pointer bugs, but continues to investigate. Users can monitor the Microsoft 365 Service health dashboard for updates on these and other ongoing issues.
Have you been affected by these Outlook issues? Share your experiences and questions in the comments below.
