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Windows XP Service Pack 1a Express Install (32-Bit) for End Users

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Windows XP Service Pack 1a (SP1a) provides security and reliability updates to the Windows XP family of operating systems. If you have already installed Windows XP SP1, you do not need Windows XP SP1a.
  • Version:


    File Name:


    Date Published:


    File Size:

    1.9 MB

      If you are not running Windows XP SP1, install SP1a for security and reliability updates to the Windows XP family of operating systems. There is no benefit to installing SP1a if you are already running Windows XP SP1. We do not recommend that you install SP1a if you are already running SP1.

      Note: Windows XP SP1a is almost identical to Windows XP SP1 except that the Microsoft virtual machine (VM) is removed in SP1a.

      Technical Changes: Windows XP SP1a does not include or install the Microsoft VM, which provides support for running Java applets.

      How to determine if you are running Windows XP SP1: From the Start menu right-click My Computer, and then click Properties. If Service Pack 1 appears under System, you are already running Windows XP SP1.

      Note: If you are running Windows XP or Windows XP SP1 with the Microsoft VM, you can continue to update the Microsoft VM by using Windows Update. If you are running Windows XP without the Microsoft VM, you do not have to install updates to the Microsoft VM. As a result, these updates are not offered to you when you visit Windows Update. Microsoft is no longer able to provide a download of the Microsoft VM for computers that do not already have the Microsoft VM installed. For more information, visit the Microsoft Technologies for Java Web site.
  • Supported Operating Systems:

    Windows XP

      1. Click the Download button on this page to start the download, or choose a different language from the drop-down list and click Go.
      2. Do one of the following:
        • To start the installation immediately, click Open or Run this program from its current location.
        • To copy the download to your computer for installation at a later time, click Save or Save this program to disk.

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