Microsoft is investigating an issue causing the Windows taskbar and Start menu to become unresponsive and triggering connection issues with Outlook and Teams.

Windows administrators told BleepingComputer that their users have reported issues with not seeing the Windows Start menu when clicked, not being able to launch modern apps, and broken Windows search.

Others have also reported experiencing issues when trying to connect to Azure Active Directory (Azure AD) to activate Office 365 applications.

Similar issues have also happened in the past with Microsoft MVP Rudy Ooms linking in June 2022 with the ClickShare application (a tool that enables wireless screen sharing of a Windows device) corrupting user shell folder registry permissions.

However, Microsoft sent a statement two months later acknowledging that its own software was breaking permissions for affected apps and causing unresponsiveness and connection issues.

“While this initially seemed to be an issue with the third-party application, it now appears to be Microsoft code (profapi.dll) breaking permissions thinking they need to be retrieved,” Redmonds told Ooms.

“This can happen when a third-party x32 process (like ClickShare) uses the Office APIs on a machine where Office is deployed using Office ClickToRun, due to a bug in the registry hooks AppvIsvSubsystem32.dll .

“In this case, profapi.dll will start to retrieve ACLs, but after a second failure, it will not write ACLs of all application packages, which will cause problems (crashes and registration failures) with packaged apps.”

Script to repair corrupt registry permissions

Today, Barco (the developer of ClickShare) updated an advisory it originally posted in July 2022 to share a Diagnostic PowerShell helper script provided by Microsoft Support that would allow affected users to repair the permissions of registry corrupt User Shell files.

“Although the app is not the root of the problem, we still want to offer our ClickShare app users a possible interim solution”, barco said.

“In most cases, recovery was possible using Microsoft’s recovery tool: FixUserShellFolderPermissions Recovery Tool.”

The script can be downloaded from Downloads section at the end of Barco’s recently updated notice.

If the issue is not resolved after running the helper script, you need to manually disable the calendar integration feature from the ClickShare Settings dialog.

“Please contact Barco support for details on a dedicated APP version (4.25.2) to prevent the issue from occurring until a final fix can be provided,” the company added.

Issue under investigation

Although Microsoft has yet to publicly acknowledge the issue, Barco said the Redmond Windows team is investigating and advises affected customers to contact Microsoft to file their own report.

“The issue is being investigated with the Microsoft Windows team, but it’s always a good idea to contact the Microsoft Windows team directly to report this issue,” Barco said.

“Make sure to mention for the ticket submission the title “start menu or taskbar not responding” and refer to Microsoft internal bug number: 41322218.”

A Microsoft spokesperson was not immediately available for comment when contacted by BleepingComputer earlier today.

H/T Gunter Born