Friday, May 10, 2013

WiX woes: What is your installer doing?

Summary: How to detect different modes of installation.
When building an application installer, it's often necessary to distinguish between different modes of installation, i.e. initial installation, repair, upgrade, uninstall, etc. And as with everything important in MSI, detecting the mode of installation is a PITA (and by PITA, I do not mean flat bread of Mediterranean origin). To help you a little bit, here is a table adopted from a StackOverflow topic (and comments), that shows the values of various Windows Installer properties can help you determine the installation mode:

Install Uninstall Repair Modify Upgrade
INSTALLED FALSE TRUE FALSE TRUE TRUE
REINSTALL TRUE FALSE TRUE FALSE FALSE
REMOVE="ALL" FALSE TRUE FALSE TRUE TRUE
UPGRADINGPRODUCTCODE TRUE FALSE TRUE TRUE TRUE

You can use logical operators NOT, AND, OR to build complex conditions.

Here is how you can detect some common conditions:

First-time installation
  • NOT Installed
Any installation
  • NOT Installed AND NOT PATCH
Installation and repairs
  • NOT REMOVE
First-time installation and repairs
  • NOT Installed OR MaintenanceMode="Modify"
Upgrades only (during uninstall phase)
  • Installed AND UPGRADINGPRODUCTCODE
Upgrades
  • Installed AND NOT REMOVE
Full uninstall (except when triggered by a major upgrade)
  • (REMOVE="ALL") AND (NOT UPGRADINGPRODUCTCODE)
Any uninstall
  • REMOVE~="ALL"
If you notice errors or want to include some other conditions, please post a comment.

See also:
MSI Property Patterns: Upgrading, FirstInstall and Maintenance
Upgrading, FreshInstall, Maintenance and other MSI convenience properties
MSI Writing Guidelines: Installation Scenarios
How to execute custom action only in install (not uninstall)