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Installation requirements for Windows Live OneCare

To ensure that your Windows Live OneCare installation runs smoothly, please review the following information:

Step 1. Make sure that your computer meets the system requirements for Windows Live OneCare

Check your computer for the following minimum requirements for successful installation. If you are unsure how to find this information, you can start the installation process and Windows Live OneCare will check your system automatically during setup. To install Windows Live OneCare, your computer must be connected to the Internet.

  • Windows® XP (Home Edition, Professional, Media Center Edition, or Tablet PC Edition) with Service Pack 2 (SP2)
  • Windows Internet Explorer 6 or 7 for Windows XP SP2 (IE 6.0.2900.2180 or 7.0.5730.11)
  • PC with 300 MHz or higher CPU clock speed
  • 256 MB of RAM
  • 550 MB of available hard disk space (on system partition)
  • 56 kbps or faster Internet connection (broadband recommended)
  • Readable/writeable CD or DVD drive (CD-RW or DVD-RW, aka "CD or DVD burner"), or external hard drive. (Necessary for Backup and Restore functionality, but not required for installing Windows Live OneCare.)

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Step 2. Uninstall other antivirus and firewall programs

This step is very important no matter what brand of protection software you use, because installing one antivirus or firewall program over another on the same computer could potentially lock up the computer.

Windows Live OneCare might not run, or it might slow the performance of your computer, if you install it when other antivirus or firewall programs are also installed on your computer. During Setup, Windows Live OneCare checks for the some common antivirus and firewall programs that are known to conflict with Windows Live OneCare and provides means for you to uninstall them.

Antivirus and firewall programs known to conflict with Windows Live OneCare:

  • Symantec Norton Internet Security 2005
  • Symantec Norton Antivirus 2005
  • Symantec Norton SystemWorks 2005
  • McAfee Internet Security Suite 2005
  • McAfee VirusScan 8.0/2004
  • Trend Micro PC-cillin Internet Security 2005

During Setup, Windows Live OneCare checks for the programs listed above and will notify you to uninstall any that are found. To avoid any potential problems, however, Windows Live OneCare recommends that you uninstall any other antivirus and firewall software (except for Windows Firewall, which is part of the Windows XP operating system and cannot be uninstalled) before beginning Windows Live OneCare installation.


  • To avoid putting your computer at risk, do not remove pre-existing antivirus or firewall software until you are ready to install Windows Live OneCare.
  • You do not need to uninstall Windows Firewall, which is a component of the Windows operating system and cannot be removed. It does not conflict with Windows OneCare; in fact, Windows Firewall provides basic firewall protection while you are removing the old software and installing Windows Live OneCare.

How do I find out if I have other antivirus or firewall software installed?

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Step 3. Make sure you are logged in as an Administrator on your computer

You need to have a user account with administrative privileges on your computer in order to install programs like Windows Live OneCare. To give yourself administrative privileges, you can either log on to the computer with the username "Administrator" (and its password), or use another account that you know has Administrator permissions.

To find out which permissions your user account has:

  1. Click Start on the Windows taskbar, then clickControl Panel.
  2. Double-click User Accounts. The listings in the Group category will tell you what kind of permissions your current account has.

To learn more about managing Windows user permission levels, click Start on the Windows taskbar, then click Help and Support.

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Release Notes

Release notes describe late-breaking issues, workarounds, and other important information you should know in order to install and run Windows Live OneCare Live successfully. Please read this page carefully.

Windows Vista (codenamed "Longhorn") beta compatibility

Currently, Windows Live OneCare can be installed only on PCs running Windows XP with Service Pack 2 (SP2).

If you install Windows Live OneCare and then upgrade your operating system to Windows Vista, Windows Live OneCare will not run on future restarts, which will leave your computer unprotected. You can install and run Windows Live OneCare on a hard disk partition running Windows XP SP2 while another partition has a different operating system such as Windows Vista. (This is known as "dual-booting.") However, Windows Live OneCare will protect only the system and files on the Windows XP SP2 partition.

Windows Live OneCare subscribers who are also participating in the Windows Vista beta program will need to run Windows Live OneCare on a different computer from the one running Longhorn. If you have only one computer, you will need to choose which product to use. If you decide to participate in the Longhorn beta instead of subscribing to OneCare, please complete the opt-out survey during the removal of the Windows Live OneCare software. Please note "Decided to test Longhorn instead of Windows Live OneCare" in your opt-out reply.

Virtual PC (VPC) compatibility

Windows Live OneCare has not been tested with Virtual PC and is unsupported in VPC environments. Subscribers who choose to install and run Windows Live OneCare on a virtual hard disk do so at their own risk. Behavior and stability is unknown, though intermittent VPC crashes have been reported.

Windows XP Professional x64 Edition compatibility

The x64-based version of Windows XP is not currently supported in Windows Live OneCare.

Updated September 30, 2020

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