The InstallInitialize action and InstallFinalize action mark the beginning and end of a sequence of actions that change the system.
The InstallInitialize action must be sequenced before any actions that change the system, such as the InstallFiles action, the WriteRegistryValues action, the SelfRegModules action, and the ProcessComponents action. The InstallInitialize action must therefore be sequenced before the InstallFinalize action and the InstallExecute action.
Custom actions that modify the Windows Installer package, for example by adding rows to a table that handles installable resources, such as the Registry table or DuplicateFile table, must be sequenced before InstallInitialize action.
There are no ActionData messages.