By Sergiu Gatlan
Publication Date: 2026-03-17 10:37:00
Microsoft is working to address a known issue that renders the classic Outlook email client unusable for users who have enabled the Microsoft Teams Meeting Add-in.
“Some users may be unable to use Microsoft Outlook Classic while the Microsoft Teams Meeting Add-in is enabled,” Microsoft said in an admin center update under EX1254044.
While it didn’t share more details about the root cause, Microsoft says the issue is due to a previous Outlook build.
To temporarily fix this bug, affected users are advised to update Outlook or to perform an Online Repair for click-to-run installs (which will reinstall all Office applications).
“Users attempting to use Microsoft Outlook Classic while the Microsoft Teams Meeting Add-in and previous Outlook build version is enabled may be impacted,” Microsoft added.
“We’ve identified that a previous Outlook build version is causing impact to occur. We’re working with your representatives to ensure that the latest Outlook version is enabled,…
