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Microsoft® Windows® Malicious Software Removal Tool (KB890830)

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This tool checks your computer for infection by specific, prevalent malicious software (including Blaster, Sasser, and Mydoom) and helps to remove the infection if it is found. Microsoft will release an updated version of this tool on the second Tuesday of each month.

Quick details

Version: 4.8 Date published: 5/8/2012
KB articles: KB890830
File name Size
Windows-KB890830-V4.8.exe 15.4 MB Download

Overview

The Microsoft Windows Malicious Software Removal Tool checks Windows Vista, Windows 7, Windows XP, Windows 2000, and Windows Server 2003 computers for and helps remove infections by specific, prevalent malicious software—including Blaster, Sasser, and Mydoom. When the detection and removal process is complete, the tool displays a report describing the outcome, including which, if any, malicious software was detected and removed. The tool creates a log file named mrt.log in the %WINDIR%\debug folder.

To download the x64 version of Malicious Software Removal Tool, click here.

This tool is not a replacement for an anti-virus product. To help protect your computer, you should use an anti-virus product.

Microsoft will release an updated version of this tool on the second Tuesday of each month. New versions will be made available through this web page, Windows Update, and the Malicious Software Removal Tool Web site on Microsoft.com.

To have the newest versions automatically delivered and installed as soon as they are released, set the Automatic Updates feature to Automatic. The version of this tool delivered by Windows Update runs on your computer once a month, in the background. If an infection is found, the tool will display a status report the next time you start your computer. If you would like to run this tool more than once a month, run the version that is available from this Web page or use the version on the Malicious Software Removal Tool Web site.

Please review KB890830 for the list of malicious software that the current version of the tool is capable of removing as well as usage instructions. Also, please be aware that this tool reports anonymous information back to Microsoft in the event that an infection is found or an error is encountered. The above KB article contains information on how to disable this functionality and what specific information is sent to Microsoft.

It is strongly recommended that you review KB891716 before you consider deploying this tool in an enterprise environment.

The user must be an administrator to run this tool. This tool will not run on any version of Windows 98, Windows ME, or Windows NT 4.0.

Note that this download is now a multi-lingual tool. For all supported languages, the same tool will show the correct language depending on the language of the operating system.

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System requirements

Supported operating systems: Windows 7, Windows Server 2003, Windows Vista, Windows XP


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Instructions

  1. Click the Download button on this page to start the download.
  2. Do one of the following:
    • To start the installation immediately, click Run.
    • To save the download to your computer for installation at a later time, click Save.
    • To cancel the installation, click Cancel.

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Windows Internet Explorer 8 for Windows XP

Internet Explorer 8 is the latest version of the familiar web browser you are most comfortable using, helping you get everything you want from the web faster, easier, more privately and securely than ever before.

  • Faster Internet Explorer 8 is more responsive with new pages and tabs, opening up fast and reliably. You can now get to the information you care about most, in fewer steps; one click access to your webmail, favorite news sites or other online services.
  • Easier Reduce the steps to accomplish many common tasks, and automate your access to real time information updates. You can keep track of your favorite sports team, news, weather with a single click.
  • More Private Helps protect your privacy and confidential information where ever you go on the web.
  • More Secure Helps protect and stop malicious software from reaching your PC, and makes it easier to detect when a website is an imposter.


Support for IE8 can be received by visiting the Internet Explorer Newsgroup to discuss issues, or by contacting Customer Support Services.

If you use a screen reader, please consult the Internet Explorer 8 release notes before downloading.
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Windows Internet Explorer 9 Enhanced with Bing & MSN

Windows Internet Explorer 9 has a streamlined look and many new features that speed up your web browsing experience. We give you more screen space to see your favorite sites, more than any other browser. The new tab page intelligently displays you most visited sites. A combined search and address bar means you can search and navigate from one place. With Pinned Sites, you can get to your favorite sites directly from the Windows 7 taskbar—without having to open Internet Explorer first. All together, making Internet Explorer the best way to browse your favorite sites.
  • Windows Vista

  • Internet Explorer 7 or later

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Windows Internet Explorer 9 Enhanced with Bing & MSN

Windows Internet Explorer 9 has a streamlined look and many new features that speed up your web browsing experience. We give you more screen space to see your favorite sites, more than any other browser. The new tab page intelligently displays you most visited sites. A combined search and address bar means you can search and navigate from one place. With Pinned Sites, you can get to your favorite sites directly from the Windows 7 taskbar—without having to open Internet Explorer first. All together, making Internet Explorer the best way to browse your favorite sites.
  • Windows 7

  • Internet Explorer 7 or later

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Windows® Defender

This is the most current release of Windows Defender. If Windows Defender informed you that an update is available, you are running an older version. We encourage you to upgrade to this version. You can check your version of Windows Defender by clicking the down arrow next to the help icon and choosing ‘About Windows Defender’.

This release includes enhanced features that reflect ongoing input from customers, as well as Microsoft’s growing understanding of the malicious software landscape.

To download the x64 version of Windows Defender, click here.

Specific features of Windows Defender include:

  • A redesigned and simplified user interface – Incorporating feedback from our customers, the Windows Defender UI has been redesigned to make common tasks easier to accomplish with a warning system that adapts alert levels according to the severity of a threat so that it is less intrusive overall, but still ensures the user does not miss the most urgent alerts.

  • Improved detection and removal – Based on a new engine, Windows Defender is able to detect and remove more threats posed by spyware and other potentially unwanted software. Real Time Protection has also been enhanced to better monitor key points in the operating system for changes.

  • Protection for all users – Windows Defender can be run by all users on a computer with or without administrative privileges. This ensures that all users on a computer are protected by Windows Defender.

  • Support for 64-bit platforms and accessibility - Windows Defender supports accessibility and 64-bit platforms. Please be sure to use WindowsDefenderX64.msi for 64-bit platforms.

  • Delta definition updates - Windows Defender now downloads smaller delta definition updates when possible which reduces the time required to download and install definition updates. Customers can expect shorter download times when updating their definition updates.

  • Free Limited Support - As a part of our commitment to the security of our customers, Microsoft is offering two free support incidents relating to Windows Defender on Windows XP and Windows Server 2003. Examples of valid support scenarios are installation, configuration, definition update, detection and removal errors. Please refer to the Windows Defender support policy for more information.

  • WGA enforcement - There are significant risks to running non-genuine Windows. Only genuine Windows customers can receive product downloads, Windows updates and special offers. Windows Defender will validate that your copy of Windows is genuine before installation. Furthermore, Windows Defender will only remove Severe threats for machines that are not genuine. Low, Medium and High threats will be detected, but not removed unless your copy of Windows is genuine. For more information, please visit The Windows Genuine Advantage.



Important Notes

  • Windows Defender no longer supports Windows 2000 as it went out of mainstream support in June 2005. Please refer to the support lifecycle website for more information.


  • Access to Newsgroups:
    In addition to phone support we also have newsgroups to help get your questions answered.

For Additional Information:
Please see the Release Notes to learn more about known issues with Windows Defender.
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Microsoft Office Compatibility Pack for Word, Excel, and PowerPoint File Formats

Users of the Microsoft Office XP and 2003 programs Word, Excel, or PowerPoint—please install all High-Priority updates from Microsoft Update before downloading the Compatibility Pack.

By installing the Compatibility Pack in addition to Microsoft Office 2000, Office XP, or Office 2003, you will be able to open, edit, and save files using the file formats in newer versions of Word, Excel, and PowerPoint . The Compatibility Pack can also be used in conjunction with the Microsoft Office Word Viewer 2003, Excel Viewer 2003, and PowerPoint Viewer 2003 to view files saved in these new formats. For more information about the Compatibility Pack, see 924074.

Note: If you use Microsoft Word 2000 or Microsoft Word 2002 to read or write documents containing complex scripts, please see 925451 for information to enable newer versions of Word documents to be displayed correctly in your version of Word.

Administrators: The administrative template for the Word, Excel, and PowerPoint converters contained within the Compatibility Pack is available for download.

Update: The Microsoft Office Compatibility Pack has been updated to include SP2. Additionally, with the updated Compatibility Pack, if .DOCX or .DOCM files contain custom XML tags, those tags are removed when the file is opened in Word 2003. For more information, please see KB978951
    Windows 7;Windows Server 2008
  • Recommended Microsoft Office programs:
    • Microsoft Word 2000 with Service Pack 3, Microsoft Excel 2000 with Service Pack 3, and Microsoft PowerPoint 2000 with Service Pack 3

    • Microsoft Word 2002 with Service Pack 3, Microsoft Excel 2002 with Service Pack 3, and Microsoft PowerPoint 2002 with Service Pack 3

    • Microsoft Office Word 2003 with at least Service Pack 3, Microsoft Office Excel 2003 with at least Service Pack 3, and Microsoft Office PowerPoint 2003 with at least Service Pack 3

    • Microsoft Office Word Viewer 2003

    • Microsoft Office Excel Viewer 2003

    • Microsoft Office PowerPoint Viewer 2003

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What happens if I don't install the Microsoft Download Manager?

Generally, a download manager enables downloading of large files or multiples files in one session. Many web browsers, such as Internet Explorer 9, include a download manager. There are many stand-alone download managers available as well, including the Microsoft Download Manager.

However, if you do not have a download manager installed, and still want to download the file(s) you've chosen, please note:

  • You may not be able to download multiple files at the same time. In this case, you will have to download the files individually from the "Thank you for downloading" page.
  • Files larger than 1 GB may take much longer to download and might not download correctly.
  • You might not be able to pause the active downloads or resume downloads that have failed.
  • Files may be more difficult to download or take longer to download.