Microsoft is investigating a new issue preventing third-party applications from launching Microsoft Office applications or opening documents on up-to-date Windows systems.
This known issue affects Word, Excel, PowerPoint, Access, and other Microsoft Office applications when launched from within the affected third-party apps.
“Microsoft has received reports of an issue in which certain third-party applications might be unable to launch Microsoft Office applications or open documents after installing the Windows updates released on or after June 9, 2026,” the company said in updated advisories.
“This issue affects certain third-party applications that use OLE automation to interact with Microsoft Office applications. In some cases, the Office application or document might fail to open without displaying an error message.”
According to user reports, the impacted third-party apps include CCH Engagement, Zotero, Workpaper Manager, dental software such as Dentrix and Softdent, and other similar applications.
While Microsoft is still working to resolve it and doesn’t yet have a fix, it advised affected customers to open the Office apps or documents directly instead of launching them from the affected third-party applications to work around this issue.
Enterprise customers can also reach out to Microsoft Support for Business for a separate workaround that they can apply across the entire organization.
“A resolution is in progress and will be included in a future Windows update. More information will be shared when it becomes available,” Microsoft added.
In recent months, Microsoft addressed an issue that prevented users of its Office for the web cloud-based productivity suite from opening Excel and PowerPoint files and another that blocked Windows 365 users from downloading and installing the Office suite.
More recently, it also fixed a known issue that caused Windows updates released since May 2025 to fail when installed using the Windows Update Standalone Installer (WUSA) and a bug that caused Windows Server 2025 devices to boot into BitLocker recovery after installing the April 2026 security update.
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