If you are on Windows 7, then you must have Windows Installer 5. Windows Installer 5.0 is available with both Microsoft Windows 7 and Windows Server 2008 R2.
Developers can use Windows Installer 5.0 to author a setup file consisting of a single installation package that is capable of either per-machine or per-user installation of the application. It is thus easy to create a dual purpose package for installing applications in windows 7 and Windows Server 2008 R2. This package can also be installed on computers running Windows Installer 4.5 or earlier. When the dual purpose package is installed on such computers, the “MSIINSTALLPERUSER” property is ignored by the previous versions of the Windows installer. Though the files and registry entries will be installed in locations accessible by other users, the package will require the computer to display UAC prompts for appropriate credentials.Thus, per user installation of software can only be achieved in Windows 7 that has the Windows installer 5.
The other major feature introduced in Windows Installer 5 is the ability to author MSI packages that can secure Windows Services, new accounts, files, folders and registry keys. The newly introduced “MsiLockPermissionsEx” table facilitates this security. To secure a registry key, file or a service, the object’s unique identifier must be specified in the table. Since this table is meant as a replacement for the “LockPermissions” table, they cannot co-exist and the installation will fail with error 1941. A package written for windows installer 5.0 can contain references to only “MsiLockPermissionsEx” table. All the earlier versions of Windows Installer i.e. versions 4.5, 3.1 etc. will ignore this table. Thus, it is only possible to secure resources in computers running windows 7 and Windows Installer 5.
The other major feature introduced in Windows Installer 5.0 is the ability to enumerate all components installed on the computer and obtain the key path to each component. This cane be achieved using the newly introduced “MsiEnumComponentsEx”, “MsiEnumClientsEx”, and “MsiGetComponentPathEx” functions.
Windows Installer 5.0 has been released with Windows 7 and Windows Server 2008 R2.The earlier version Windows Installer 4.5 was available as a redistributable for Windows Vista RTM and Service Pack 1, Windows XP Service Pack 3 and SP2, Windows Server 2008 RTM/SP1 and Windows Server 2003.
Unlike Windows Installer 5, Windows Installer 4.5 did not support the aforementioned features like the creation of a dual purpose installation package or the ability to customize the services on a computer.
Windows Installer 5 is not available as a standalone version and you can either download Windows 7 SDK Web installer or the Windows 7 SDK ISO file. The advantage of the web installer is you can choose to install any subset of the SDK. It however requires you to be connected to the internet. The ISO file is a complete package and it can even be installed on a computer not connected to the internet.
Get Windows 7 and enjoy the new capabilities in Windows Installer 5. Note that windows 7 free download is available for students of schools enrolled in MSDN AA (Microsoft Developer Network Academic Alliance) program and free Windows 7 upgrade is available for buyers of windows vista.
One can also download windows enterprise trial version and use it for 90 days to experience the greatest and the latest OS from Microsoft, before buying it.
You can also download redistributable version of windows Installer 3.1, for earlier versions of windows like Windows XP.