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Article ID: 946265 - Last Review: January 16, 2015 - Revision: 6.0

This article has been archived. It is offered "as is" and will no longer be updated.

Windows Live OneCare is no longer available for sale

Existing subscribers will continue to be supported throughout the term of their subscriptions. Existing subscribers can reinstall by following the steps to download a trial ( , and can still add a PC to their existing OneCare circle ( .

Learn more about end of sale for OneCare ( ) .

On September 29th 2009, Microsoft introduced Microsoft Security Essentials, a FREE consumer anti-malware solution for Genuine Windows based PCs.

Learn more about Microsoft Security Essentials or download from Microsoft directly at: ( .

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When you try to install Windows Live OneCare and Microsoft Forefront Client Security on the same computer, the second product that you try to install cannot be installed. The symptoms that you experience depend on the scenario in which you try to install the product.

Scenario 1

When you try to install Windows Live OneCare on a computer that has Forefront Client Security installed, the installation of Windows Live OneCare fails. Additionally, you receive the following error message:
OneCare installation could not complete.
One or more components of Windows Live OneCare did not install successfully. Please contact support for assistance with correcting this issue.
Error ID: 0020-80070643

Scenario 2

When you try to install Forefront Client Security on a computer that has Windows Live OneCare installed, the installation of Forefront Client Security fails. Additionally, you experience the following symptoms:
  • When you use the Clientsetup.exe command-line program, the program exits, you receive the following error message:
    Microsoft Forefront Client Security -- Installation failed.
    See log 'C:\Program Files\Microsoft Forefront\Client Security\Client\Logs\Clientsetup.log' for more information.
  • When you call the command line program (Clientsetup.exe) programmatically from a script or from a batch file, the following error level is returned:
  • The following information is logged in the Clientsetup.log file:
    Time Microsoft Forefront Client Security (<versionnumber>) -- Installation started
    Time Hardware requirement check passed.
    Time OS requirement check passed.
    Time Software requirement check passed.
    Time Microsoft Windows OneCare Live has been found. Please remove that product and rerun client setup.
    Time Microsoft Forefront Client Security -- Installation failed.
  • The following event is logged in the Application event log:

    Event Type: Error
    Event Source: MsiInstaller
    Event Category: None
    Event ID: 11724
    Description: Microsoft Forefront Client Security -- Installation failed. For more information, see Help and Support Center at


Windows Live OneCare and Forefront Client Security are anti-malware products. Therefore, you cannot install both products on the same computer.


If you want to change the anti-malware program that you use, first uninstall the anti-malware program that is already installed. Then, install the anti-malware program that you want to use.

More information

Forefront Client Security is malware protection software designed for businesses, and Windows Live OneCare is designed for consumers. Both products have different features to meet the needs of the corresponding target group.

If a university or an employer has licensed Forefront Client Security with home usage rights, you may be able to install Forefront Client Security on a home computer. If you already use Windows Live OneCare, you must decide which product you want to use. In this case, contact your corporate help desk or your university help desk to determine the following:
  • Whether you can create a VPN connection to the network
  • Whether the VPN connection requires a specific anti-malware product to be installed
For more information about Forefront Client Security, visit the following Microsoft Web site: (

Applies to
  • Microsoft Forefront Client Security
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