Microsoft Outlook for Mac users running version 16.110, build 26061317, are experiencing a bug that prevents the inclusion of original message threads in email replies and forwards. According to documentation on Microsoft Learn, the issue was introduced in the June 16 update. A moderator identified as Microsoft external staff confirmed the bug and currently recommends rolling back to version 16.109.3 to restore standard functionality.
Why Does the Missing Thread Bug Matter?
The absence of conversation history impacts both productivity and standard business communication, according to user reports on official Microsoft forums. When a user hits “Reply” or “Forward,” the composition window remains blank, stripping away the context required for professional correspondence. As one user noted on the Microsoft Learn platform, the failure to include original messages effectively “defeats the purpose” of the forwarding function, complicating workflows that rely on threaded history for project tracking.
How to Revert to a Previous Outlook Version
To resolve the issue, users must uninstall the current version and perform a clean installation of an earlier build. Microsoft Learn documentation directs users to install version 16.109.3 or older. Because the software may attempt to automatically re-update to the broken version, users must disable the automatic update feature. To do this, navigate to the “Help” dropdown menu, select “Check for Updates,” and uncheck the box labeled “Automatically keep Microsoft apps up to date.”
The Future of Version Control in Enterprise Software
This incident highlights the tension between rapid software deployment and core functionality stability. While Microsoft frequently pushes updates to address security vulnerabilities, the June 16 release demonstrates how a single build can disrupt fundamental communication tools. Unlike previous software cycles where users could delay updates for months, modern cloud-connected applications often force updates, leaving users with little recourse when a bug occurs. Industry analysts often contrast this “evergreen” update model with legacy software, where version stability was prioritized over frequent feature iterations.
Frequently Asked Questions
Is there an official fix available for the Outlook reply bug?
As of June 22, 2026, Microsoft has not announced a specific timeline for a permanent fix, according to reporting by The Register.
What should I do if I cannot roll back my version?
Users on managed devices should contact their internal IT support team. If you are an individual user, you must wait for Microsoft to release a subsequent update that addresses the build 16.110 regression.
Should I re-enable automatic updates after the fix?
Yes. Once a stable version is released, it is critical to re-enable automatic updates to ensure your machine receives the latest security patches and performance improvements.
Are you currently experiencing this bug in your Outlook workflow, or have you found a different workaround? Share your experiences in the comments below, or subscribe to our newsletter for the latest updates on Microsoft software developments.
