Microsoft's June Windows 11 update breaks Office automation and more</final

Businesses that rely on Office-connected software are facing the most immediate disruption from Microsoft’s June Windows 11 update. After installing KB5094126, some applications have been unable to open Word through COM automation, throwing HRESULT 0x80020005, or DISP_E_TYPEMISMATCH, during Documents.Open() calls. That is the kind of failure that can stop accounting systems, document workflows and other third-party tools from handing off work to Word without giving ordinary users a clear explanation.

Microsoft released KB5094126 on June 9 for Windows 11 versions 25H2 and 24H2, with OS builds 26200.8655 and 26100.8655. The cumulative update includes the latest security fixes and non-security changes from the prior month’s optional preview release, but it has quickly become a reliability problem instead of a routine Patch Tuesday install. Microsoft’s own release notes now tell users to check the Windows release health dashboard for the latest status on the patch.

The list of complaints has widened beyond Office automation. Microsoft’s Windows 11 version 25H2 release-health page now lists a confirmed KB5094126 issue in which deleting a file from the Recycle Bin can show an internal filename in the confirmation dialog. That issue was last updated on June 18, and Microsoft says affected organizations can get a workaround through Microsoft Support for business.

Separate Microsoft Q&A posts from mid-June also describe more serious failures: BitLocker recovery loops, computers that would not boot properly after installing KB5094126, and corporate tablets forced back into recovery after the June 9 update. Together with the Word automation break, the reports suggest the patch is touching both consumer-facing functions and core device-management behavior on the same release line.

For Microsoft, the deeper problem is trust. Windows updates are supposed to harden systems without interrupting work, yet KB5094126 has forced IT teams to weigh security gains against the risk of breaking standardized PCs and Office-linked workflows. That calculation is especially stark for organizations that run Windows as critical infrastructure, where a faulty update can create support costs, delay operations and undermine confidence in the patch process itself.