ACTIVE SETUP AND HOW TO IMPLEMENT IT 

Written by Ed Tippelt, ert@pobox.com, copyright 2001-PRESENT

Active setup is a process that runs automatically when a user logs in.

Registry keys at 

HKLM\Software\Microsoft\Active Setup\Installed Components\%APPNAME% 
and 
HKCU\Software\Microsoft\Active Setup\Installed Components\%APPNAME% 

are compared, and if the HKCU registry entries don't exist, or the
version number of HKCU is less than HKLM, then the specified 
application is executed for the current user. 

If your application requires installation of components such as 
files or registry keys on a per-user basis, but your application 
has no advertised entry points or other triggers to initiate the 
installation process, then Active Setup is the solution. 

To implement Active Setup, you need to package all your user 
installation requirements into an EXE preferably, 
using SMS Installer, or Wise Installation System for example, 
and place the EXE on the client workstation 
during the main application installation process. 

In addition, populate the following registry key with two ( REG_SZ ) values: 

KEY: 
HKLM\SOFTWARE\Microsoft\Active Setup\Installed Components\%APPNAME% - 
where %APPNAME% is an arbitrary string which can be the application name,
or its product code GUID if using an MSI. 
(As long as it is unique on that workstation!)

VALUE1: 
StubPath=<full local path>\YourActiveSetup.exe 

VALUE2: 
Version=1 

(If using more complex version numbers, use a comma as delimiter and not
a period, eg: 1,0,3 not 1.0.3)

You can also add a string to the Default value for this key, to describe
the Active Setup, as this string will be displayed when Active Setup runs.

When each user logs on for the first time after an Active Setup has been
configured in HKLM, the operating system compares Active Setup
keys between HKLM and HKCU, and runs the nominated executable if the
HKCU entry is missing or the version in HKCU is less than HKLM. 
So if you ever need to update the ActiveSetup executable, just install
a new version, and increment the Version registry key (VALUE2 above)
in HKLM. Next time the user logs on, the active setup will run again
for that user. 

To force a repair using the existing MSI where a separate Active Setup
EXE is not required, you can do it this way:

Create the following key structure under HKEY_LOCAL_MACHINE hive:
HKEY_LOCAL_MACHINE\Software\Microsoft\Active Setup\Installed Components\[ProductCode]
Under this registry key, create a <new string value> such as:
"StubPath"="msiexec /fauvs {ProductCode} /qb"
The MSIEXEC options can be found in the help file MSI.CHM, which is
part of the windows installer SDK.

Finally, it is possible to define the order in which Active Setup commands
are run - the clues are in the registry so I will leave it to you to
figure this out!  (Or you can email me...)