FAQ
What does Legacy Update run on?
| Operating System | Compatibility | |
|---|---|---|
| Windows 2000 Professional Windows 2000 Server | Supported on any edition of Windows 2000. Requires SP3 or SP4 and Internet Explorer 6. Legacy Update will install these for you automatically if needed. |
| Windows XP Windows XP Embedded Windows Fundamentals for Legacy PCs Windows Embedded 2009 Windows Server 2003 Windows Server 2003 R2 Windows Home Server 2007 | Supported on any edition and service pack of Windows XP, Server 2003, and Embedded 2009. You can optionally upgrade to SP3 via Legacy Update setup. Includes Itanium editions. Known issues: You may need to use a workaround to start Legacy Update setup, due to a bug in Windows XP/Server 2003. On Windows Server 2003/2003 R2, checking for updates for the first time may take up to 30 minutes. Please be patient for this to complete. If you get the error message “External cab file processing completed with some errors”, simply try checking for updates again. |
| Windows Vista Windows Server 2008 | Supported on any edition of Windows Vista or Server 2008 with SP2 and a certain set of required updates. Legacy Update will install these for you automatically if needed. You can also optionally install Internet Explorer 9. Includes Itanium editions. Known issues: Checking for updates for the first time may take 30+ minutes. Please be patient for this to complete. Having Office 2010 installed may cause checking for updates to never complete. |
| Windows 7 Windows Embedded 7 Windows Thin PC Windows Server 2008 R2 Windows Home Server 2011 | Supported on any edition of Windows 7 or Server 2008 R2 with SP1 and a certain set of required updates. Legacy Update will install these for you automatically if needed. Known issues: Having Office 2010 installed may cause checking for updates to never complete. |
| Windows 8 Windows 8.1 Windows Embedded 8 Windows Embedded 8.1 Windows Server 2012 Windows Server 2012 R2 | Supported on any edition of Windows 8/8.1 and Server 2012/2012 R2 with a certain set of required updates. Legacy Update will install these for you automatically if needed. Upgrading from Windows 8 to Windows 8.1 is recommended. This requires some manual steps - Legacy Update can’t do this for you. |
| Windows 10 Windows 11 Windows Server 2016, 2019, 2022 Windows Server 2025 | Supported on any edition of Windows 10/11 and Server editions based on it, including Windows Insider preview builds. Legacy Update will only function as an alternative user interface you can access the Windows Update service, and won’t otherwise make changes to your system. Accessible via Microsoft Edge in Internet Explorer mode, or you can open Legacy Update in Internet Explorer through the Start menu shortcut. |
| Windows 95, 98, Me Windows NT 3.x/4.x | Earlier versions of Windows are currently not supported by Legacy Update. Try Windows Update Restored instead, another community project that aims to provide updates for earlier versions of the Windows Update service. |
| Windows 8 RT Windows 8.1 RT | Legacy Update is currently not supported on Windows 8/8.1 RT (ARM-based) tablets, due to the unique security features of this version of Windows. Please note that this only applies to a small range of tablets - most Windows 8/8.1 tablets use typical Intel/AMD x86-64 processors. |
| Windows CE Windows Mobile Windows Phone | Mobile editions such as Windows CE and Windows Phone are currently not supported by Legacy Update. They may work if manually configured to check for updates from Legacy Update’s proxy server. |
Legacy Update runs on 32-bit (x86), 64-bit (x86-64 or x64), and Itanium (IA64) editions of the above operating systems.
Legacy Update does not officially provide support for beta/unreleased versions of Windows. They may receive some updates, but most were removed a long time ago, or will not be suitable for the build you’re running.
Known compatibility issues
Windows XP/Server 2003: You may need to use a workaround to start Legacy Update setup, due to a bug in Windows XP/Server 2003.
Windows Server 2003/2003 R2: Checking for updates for the first time may take up to 30 minutes. Please be patient for this to complete. If you get the error message “External cab file processing completed with some errors”, simply try checking for updates again.
Windows Vista, 7, 8, 8.1: Checking for updates for the first time may take between 30 - 60 minutes. Please be patient for this to complete.
Office 2010: Having Office 2010 installed may cause checking for updates to never complete. There is a workaround available.
Windows 95, 98, Me, and NT 4
Legacy Update focuses on version 6 of Windows Update. It works because we’re lucky enough that the “v6” protocol is still in use today with Windows 10/11. As such, it simply proxies all protocol traffic to Microsoft’s official Windows Update servers. It seems unlikely that Microsoft will completely discontinue Windows Update for 2000/XP. Earlier versions of Windows never received Windows Update v6, and all versions prior to v6 are now discontinued, making a reimplementation of them more difficult.
Fortunately, we work with the Windows Update Restored project, who have revived many of these earlier versions of Windows Update. Check out their work if you’re interested in these earlier versions of Windows.