Identifying installed updates on Microsoft products (888535)

SUMMARY

This paper explains the standard developed by the Microsoft Sustained Engineering (SE) Baseline Effort to track installed updates. The SE Baseline Effort is responsible for setting standards for Sustained Engineering practices at Microsoft.

When an update is installed, details of the installation are added to the system. These details enable the installation to be traced after the installation is completed. Regardless of whether the update is applied by using Update.exe or by using the Microsoft Windows Installer, the same information is tracked.

The information in the following table is typically tracked for updates.

Value	Example value	Comments
Package Name	Security Update for Windows Server 2003 (KB123456)
Package Version	1	For more information about package versions, see 824686.
Publisher	Microsoft Corporation
Publishing Group	Windows Sustained Engineering
Release type	Security Update	For more information about release types, see 824684.
ARP Link	`HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall`	Links to ARP entries are only tracked to updates installed by Update.exe.
Installed By	JohnSmith
Installed Date	9/18/2003
Installer Name	Update.exe	This value identifies the installer as Update.exe or Windows Installer.
Installer Version	5.3.16.6

Notes

Some updates that are installed with Update.exe also include file details to identify the installer. However, file details that are in the registry are frequently out of date because subsequent installations may replace those files. We do not recommend that you use the file details that are provided in the registry to identify a fix or to determine whether a fix is appropriately installed. Instead, we recommend that you examine the actual files.
Typically, there is parity between Update.exe and Windows Installer regarding what is tracked in the file details. The primary difference between the two methods is that the Add/Remove Programs link is not recorded for Windows Installer updates.

Viewing installed updates

Depending on the method that is used to install the update, you can find the tracking information in one of two locations. For Update.exe, the details are stored in the registry. For Windows Installer, the details are stored in the Windows Installer installer database tables.

Update.exe updates

For the Update.exe installer, update information is tracked under the registry key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Updates\. Each product creates its own subkey that contains details of its installed updates. The individual product teams create subkeys that describe the type of service releases that they produce. Some product groups may not release service packs. Because some updates may supersede others, you should use the file details themselves and not the registry information to determine a specific file installation.

Windows Installer updates

For updates installed through Windows Installer, the information is tracked in the update package and is available through the Windows Installer interfaces. Within the update package, most details of the installed update are stored in the MsiPatchMetadata table within the Microsoft extensions section.

For more information about Windows Installer updates, visit the following Microsoft Developer Network (MSDN) Web sites:

MsiEnumPatches
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/msienumpatches.asp

MsiPatchMetaData
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/msipatchmetadata_table.asp

GetUserNameEx
http://msdn.microsoft.com/library/en-us/sysinfo/base/getusername.asp