If you are in a situation where you can not upgrade to Windows Installer 4.5 or higher, there is a way to install AutoTag and AutoTag Max with Windows Installer 3.1.
You'll need to install the prerequisites and then run the msi installer, not the exe installer.
a) J# Redistributable 2.0 SE (http://www.windwardreports.com/vjredist.htm)
b) If you are running Office 2000, 2002, 2003
c) If you want to test the scheduling capabilities of AutoTag Max, you will either need access to an installation of Sql Server.
2) Download and run the AutoTag or AutoTag Max 'Windows UPGRADE program (MSI)' from http://www.windwardreports.com/downloads.htm. They have been highlighted them in the screenshot.
Note: this has been tested and verified on a Windows XP SP3 machine with Windows Installer 3.1 and Office 2003.