Table of Contents
- Why Is Microsoft Outlook Crashing After June 2025 Updates? Critical Fix Inside
- Critical Security Updates Trigger Widespread Issues
- Affected Versions and Root Causes
- Microsoft’s Official Response and Workaround
- Temporary Fix Implementation
- User Feedback and Effectiveness
- Additional Known Issues
- Enterprise Impact and Recommendations
Why Is Microsoft Outlook Crashing After June 2025 Updates? Critical Fix Inside
Microsoft Office users experienced significant disruptions following the June 2025 security updates, with Classic Outlook crashing unexpectedly across multiple versions and deployment methods. These crashes affected both MSI and Click-to-Run installations, creating widespread productivity issues for enterprise and individual users alike.
Critical Security Updates Trigger Widespread Issues
The June 10, 2025 security updates addressed several critical remote code execution vulnerabilities, including CVE-2025-47162, CVE-2025-47164, CVE-2025-47167, and CVE-2025-47953, all rated with a CVEv3 score of 8.4. These vulnerabilities were particularly concerning because exploitation required only displaying content in the preview window, making them highly exploitable attack vectors.
However, the security patches introduced unintended consequences. Users across different Office versions began reporting immediate crashes when performing basic email operations:
- Double-clicking emails caused instant application termination
- Creating new messages triggered immediate crashes
- Opening existing emails resulted in application failure
Affected Versions and Root Causes
The crashes impacted multiple Office configurations:
- Office 2021 LTSC: Users reported crashes when handling emails, with no corresponding entries in Windows event logs.
- Office 2016: The security update KB5002683, designed to fix CVE-2025-47171, emerged as the primary culprit for MSI installations.
- Office 365 Click-to-Run: All versions from Office 2016 onwards experienced similar issues, including version 2408 build 17928.20572 from the semi-annual channel.
- Monthly Enterprise Channel: Microsoft officially confirmed crashes affecting version 2504 (build 18730.20122) and later versions.
Microsoft’s Official Response and Workaround
Microsoft acknowledged the issues through multiple support documents, confirming that crashes occur because Outlook cannot access the Forms Library. The company identified that a critical FORMS2 folder was missing from user profiles, particularly affecting virtual desktop infrastructure (VDI) environments.
Temporary Fix Implementation
Microsoft provided a straightforward workaround requiring users to manually create the missing folder:
- Close all Office applications completely
- Navigate to the Run dialog (Windows key + R)
- Enter the path: %localappdata%\Microsoft
- Create a new folder named “FORMS2”
- Restart Outlook to test functionality
The complete folder path should be: C:\Users\<username>\AppData\Local\Microsoft\FORMS2
User Feedback and Effectiveness
Community feedback regarding the workaround has been mixed but generally positive. Enterprise administrators successfully deployed the fix via Group Policy Objects (GPO), allowing Outlook LTSC 2021/2024 (both x86 and x64 versions) to function normally.
However, some users reported persistent issues:
- Incomplete crash prevention in certain configurations
- Image forwarding problems where embedded photos display as “The linked image cannot be displayed”
- Performance degradation in shared mailbox scenarios
Additional Known Issues
Microsoft is simultaneously investigating several related problems:
- Shared mailbox folder flickering when moving items between folders (version 2505, build 18827.20128)
- Calendar access issues with Global Address List contacts
- Desktop shared calendar improvements causing various complications
Enterprise Impact and Recommendations
The crashes particularly affected corporate environments using virtual desktop infrastructure, highlighting the critical nature of thorough testing before deploying security updates. Organizations should:
- Test updates in isolated environments before enterprise-wide deployment
- Implement the FORMS2 folder creation proactively via GPO
- Monitor user reports for additional symptoms or workaround failures
- Consider staged rollouts for future security updates
Microsoft continues investigating the root cause while working on a permanent solution. The company has escalated the issue internally and promises updates as more information becomes available.