A common question I have been receiving lately is about the Windows Installer 3.1 (v2) Redistributable and what version of the Windows Installer is actually the "latest". Well, let's hope that this posting clears up any confusion on the topic. :)
 
There are actually three versions of Windows Installer 3.1 that have been released:
 
3.1.4000.1823   This version is installed with the original Windows Installer 3.1 (v1) redistributable.
3.1.4000.1830   This version is the version that shipped with Windows Server 2003 Service Pack 1.
3.1.4000.2435   This is the latest version and contains a fix to address the issue in KB898628.
 
It's important to note that 3.1.4000.1823 and 3.1.4000.1830 are functionally identical. The reason why the version numbers are different is because the final build of Windows Server 2003 Service Pack 1 was made a few days later than the final build of our original redistributable package.
 
Now that you know all the version information, let's discuss how you can ensure that you have the latest version:
 
Both the original version of Windows Installer 3.1 (3.1.4000.1823) as well as the updated version (3.1.4000.2435) were sent out through Windows Update as critical updates. If you use Windows Update to automatically update your machine, you should already have the latest version.
 
If you want to check the version of the Windows Installer on your system, check the version of MSI.DLL in the Windows\System 32 folder. If the version is 3.1.4000.2435, you have the latest version.
 
One common point of confusion is that even if you have the latest version of Windows Installer 3.1 on your system and you type in msiexec.exe /? from a command-window, you will still be told that you are on version 3.1.4000.1823 or 3.1.4000.1830. This is because msiexec.exe /? will only give you the version of msiexec on the system -- not the other Windows Installer-related dll's. (The version of msiexec was not updated to 3.1.4000.2435 with the (v2) redistributable, just msi.dll was updated.)
 
If you find that the version of MSI.DLL on your system is not 3.1.4000.2435, the easiest way to get to the newest version is to go to Windows Update and download the update. If you need to manually download the update, you can visit KB898715 for Windows Server 2003 SP1 and 64-bit Windows XP systems or KB893803 for other supported platforms.
 
 
[Author: Tyler Robinson]
 
This posting is provided "AS IS" with no warranties, and confers no rights. Use of included script samples are subject to the terms specified at http://www.microsoft.com/info/cpyright.htm.