Appendix G: Detect the Version of WSUS

Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2, Windows Server 2008, Windows Server Update Services

The way you detect the version of a WSUS installation has changed in WSUS 3.0. In previous versions, WSUS used Microsoft© Windows© Installer product keys. In WSUS 3.0, versioning is persisted in the registry to support new installer technologies such as CBS for Windows Vista® and Windows Server® 2008.

Versioning in SUS 1.0

Check for the install state of the following Windows Installer product key:



SUS 1.0 must be removed before installing WSUS 3.0.Upgrade between these two versions is not supported.

Versioning in WSUS 2.0

Check for the install state of the following Windows Installer product key:


In WSUS 2.0, the WSUS registry key:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Update Services\Server\Setup

has an InstallType subkey with the following possible values:

Frontend = 32

Backend = 64

FullInstall = 128


You can upgrade from WSUS 2.0 to WSUS 3.0 for installations with the Frontend and FullInstall values. For the Backend value, you would uninstall WSUS, leaving the database behind. This database will be upgraded when the front-end WSUS server that points to the database is upgraded.

WSUS 3.0 pre-release candidate versions

Versions of WSUS 3.0 that precede the first release candidate version also have Windows Installer product keys. There is one product key for 32-bit architectures and another for 64-bit architectures.

{BCE8923B-20C9-4EBD-AB18-31CDC13B92E6} (x86)

{2E3FC5F0-0415-4e75-A3D3-74077F809FDD} (x64)

WSUS 3.0 Release Candidate 1 and later versions

For WSUS 3.0, there is no Windows Installer product key, but there are two registry values: InstallType supports only two installation types: 1 = install or 2 = console-only install. VersionString is a string of the form Major.Minor.Build.Revision.

To detect WSUS versions

  1. Check that SUS 1.0 and WSUS 2.0 are not installed (by looking for the product keys).

  2. Find the registry key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Update Services\Server\Setup.

  3. Check the InstallType values (32/64/128 if WSUS 2.0, 1/2 if WSUS 3.0).

  4. Check for VersionString values.