Windows update issue that impacts CRM versions
Windows logos

Important issue with recent Windows update - Impacts all Efficy versions

Microsoft is aware of this issue and is working on a resolution and will provide an update in an upcoming release.


A follow-up to our message related to the Windows updates KB4056890 to KB4056899.

Microsoft has recently published corrections for the bug it introduced in the Windows updates mentioned above, which also affected Efficy.

- For Windows 10 Build 1709: KB4073291

- For Windows 10 Build 1703: KB4057144

- For Windows 10 Build 1607: KB4057142

- For Windows 8.1, Windows Server 2012 R2: KB4057401

This means that from our side no further action is required, in due course everything will be solved via the Windows update system.

There is a huge problem with the recent Windows updates KB4056890 to KB4056899 (the actual KB number depends on the Windows version you’re running) released a couple of days ago by Microsoft.

The update introduces a major bug in the Windows “CoInitializeSecurity” function that is used by Efficy. On the Efficy server it may prevent access to the scripting, or may prevent communication with the COM+ server. On a user computer it disturbs the communication between Windows Explorer and the Sidebar. All past and present Efficy versions are impacted.

Please do not install this Windows update on your computer or on any Efficy server.

Microsoft is aware of this issue and “is working on a resolution and will provide an update in an upcoming release”.

For more details for Windows 10 see Windows 10 Improvements and fixes

For Windows 2012 Server see Windows Server 2012 Improvements and fixes

We apologize for the inconvenience.