If you receive a Windows Update error, try Solutions for common Windows Update errors.

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If your problem isn't solved, update the Windows Update Agent to the latest version. There is no stand-alone Windows Update Agent available to download. If you have automatic updating turned on, the latest version of the Windows Update Agent is downloaded and installed automatically on your computer.

If you do not have automatic updating turned on, follow these steps to obtain the latest version of the Windows Update Agent:
  1. Turn on automatic updating. To do this, follow these steps, as appropriate for the version of Windows that you are running.

    Windows 8.1 or Windows 8
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    1. Open Windows Update by swiping in from the right edge of the screen (or, if you're using a mouse, pointing to the lower-right corner of the screen and moving the mouse pointer up), tapping or clicking Settings, tapping or clicking Control Panel, and then tapping or clicking Windows Update.
    2. Tap or click Change settings.
    3. Under Important updates, choose Install updates automatically.
    4. Under Recommended updates, select the Give me recommended updates the same way I receive important updates check box, and then click OK.
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    Windows 7, Windows Vista, or Windows XP
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    To turn on automatic updating automatically, click the Fix it button or link, and then click Run in the View Download dialog box. Then, follow the steps in the Fix it wizard.

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  2. Restart the Windows Update service. To do this, follow these steps:
    1. Press the Windows logo Key+R to open the Run box.
    2. Type services.msc in the Run box, and then press Enter.
    3. Right-click Windows Update in the Services management console, and then click Stop. If you are running Windows XP, right-click Automatic Updates, and then click Stop.
    4. After Windows Update stops, right-click Windows Update, and then click Start. If you are running Windows XP, right-click Automatic Updates, and then click Start.
  3. Wait for Windows Update to start, and then verify that the Windows Update Agent is updated. For more information about how to check which version of the Windows Update Agent is installed, go to the "How to check which version of the Windows Update Agent is installed" section in this Microsoft Knowledge Base (KB) article.

How to check which version of the Windows Update Agent is installed

  1. Open the %systemroot%\system32 folder. %systemroot% is the folder in which Windows is installed. For example, the %systemroot% folder is C:\Windows.
  2. Right-click Wuaueng.dll, and then click Properties.
  3. Click the Details tab, and then locate the file version number.
Note The latest version of the Windows Update Agent for Windows 8.1 is 7.9.9600.16422. The latest version of the Windows Update Agent for Windows 8 is 7.8.9200.16693. The latest version of the Windows Update Agent for Windows 7, Windows Vista, and Windows XP is 7.6.7600.256.

For more information

Historical Information

Improvements in version 7.6.7600.256 of the Windows Update Agent
  • A hardened infrastructure so that the Windows Update client will trust only those files that are signed by a new certificate. The certificate is used solely to protect updates to the Windows Update client.
  • A more secure communication channel for the Windows Update client
Improvements in version 7.4.7600.226 of the Windows Update Agent
  • Improved scan times for Windows updates
  • Improved Windows Update UI for computers that are running Windows Vista or Windows Server 2008
  • More visible and detailed descriptions of updates
  • Improvements in how users are notified about service packs
Issues that are fixed in version 7.2.6001.788 of the Windows Update Agent
Version 7.2.6001.788 of the Windows Update Agent fixes the following issue. This issue was not previously documented in a Microsoft Knowledge Base article:
  • When you try to install 80 or more updates at the same time from Windows Update or Microsoft Update, you receive a "0x80070057" error code.
Improvements in version 7.2.6001.784 of the Windows Update Agent
  • Improved scan times for Windows Update
  • Improved speed at which signature updates are delivered
  • Support for Windows Installer reinstallation
  • Improved error messaging
Issues that are fixed by version 7.0.6000.381 of the Windows Update Agent
Version 7.0.6000.381 of the Windows Update Agent fixes the following issues. These issues were not previously documented in a Microsoft Knowledge Base article:
  • The Background Intelligent Transfer Service (BITS) crashes on a Windows Vista-based computer. For more information, see An update is available to fix a Background Intelligent Transfer Service (BITS) crash on a Windows Vista-based computer .
  • A fix is included that reduces the number of restarts that are required for the stand-alone installer when Multilingual User Interface Pack (MUI) files are being used.
  • User interface elements in the Korean, Simplified Chinese, and Traditional Chinese languages are fixed.
  • The Windows Vista installation experience is improved.

More information about Windows Update

Windows Update helps keep your computer up-to-date and secure by downloading and installing the latest security and other updates from Microsoft. Windows Update determines which updates apply to your computer.

Microsoft periodically makes software updates available to users of Windows and other Microsoft software. These include updates that improve reliability and performance, updates that provide new protections against malware and other potentially unwanted software, and upgrades to Windows features. To improve the performance or the reliability of hardware components on the computer, Microsoft may also provide updates to device drivers that are supplied by the computer manufacturer.

If you turn on Windows Update, software components that are directly related to Windows Update will have to be updated occasionally on your computer. These updates must be performed before Windows Update can check for required updates or before it can install other updates. These required updates fix errors, provide ongoing improvements, and maintain compatibility with the Microsoft servers that support Windows Update. If you disable Windows Update, you will not receive these updates.

Windows Update is configured to install updates automatically when you select the recommended option during Windows Out Of Box Experience (OOBE) Setup. You can also turn on Windows Update by selecting one of following settings in the Automatic Updates item in Control Panel:
  • Automatic (recommended)
  • Download updates for me, but let me choose when to install them
  • Notify me, but don't automatically download or install them
After you turn on Windows Update, the required updates to components of Windows Update will be downloaded and installed automatically without notifying you. This behavior occurs regardless of which setting you use to turn on Windows Update. If you do not want to receive required updates, you can disable automatic updates in Control Panel.

The updates to Windows Update itself typically do the following: Address feedback from customers, improve compatibility, service performance and reliability, and enable new service capabilities. When the Windows Update server is updated, a corresponding client update is typically required. During an agent self-update operation, Windows Update Agent files may be added, modified, or replaced. For example, Windows Update Agent files that help display the user experience or that determine whether updates apply to a particular system may be added. This behavior occurs when a system is set to automatically check for available updates. This does not occur when automatic updates are turned off. For example, this behavior does not occur if you select Never check for updates in Windows Vista and Windows 7 or if you select Turn off Automatic Updates in Windows XP.

Information for administrators of managed environments

Administrators will receive the latest version of the Windows Update Agent for deployment through Windows Server Update Services (WSUS).

About this article

Article ID: 949104
Last review: May 23, 2014
Applies to: Microsoft Update
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