MSP and Custom Actions

Question

Suppose that MSI has custom action as part of the installation and custom action for the uninstall.

What should happen if I build MSP for that MSI - if I instal the MSP, will it re-run the custom action? What happen if the custom action itself is changed?

Answer 1

Applying or uninstalling a patch will run the InstallExecuteSequence similar to maintenance mode, so an action will run depending on its sequence conditions. With the exception of the actions with the MSI 4.5 patch-uninstall flag, the current version of the custom action (the patched version when installing the patch, and the previous version when uninstalling the patch) is used.