Error message when you run a beta version of Windows Defender: "Application failed to initialize: 0x800106ba"

Retired KB Content Disclaimer

This article was written about products for which Microsoft no longer offers support. Therefore, this article is offered "as is" and will no longer be updated.


When you run the prerelease (beta) version of Windows Defender, you may receive the following error message:
Application failed to initialize: 0x800106ba. A problem caused this program's service to stop. To start the service, restart your computer or search Help and Support for how to start a service manually.


This problem occurs because the beta version of Windows Defender expired on December 31, 2006. When you try to start the Windows Defender service after this date, you receive the error message that is mentioned in the "Symptoms" section.


To resolve this problem, use one of the following methods.

Windows XP and Windows Server 2003

To resolve this problem in Microsoft Windows XP or in Microsoft Windows Server 2003, install the release version of Windows Defender to continue protecting your computer. For more information about the release version of Windows Defender, visit the following Microsoft Web site:

Windows 2000

To resolve this problem in Microsoft Windows 2000, uninstall Windows Defender. Windows Defender is not supported in Windows 2000.

Article ID: 930522 - Last Review: Jul 1, 2010 - Revision: 1