Question

How can I pass the installation directory info to the custom action exe?

Answer

See MSDN Topics:
Changing the Target Location for a Directory [Windows Installer]
MsiSetTargetPath(MSIHANDLE,LPCTSTR,LPCTSTR) function [Windows Installer]
TARGETDIR property [Windows Installer]
Using the Directory Table [Windows Installer]
Specifying Directory Structure [Windows Installer]
Working with Folder Locations [Windows Installer]
Custom Action Type 35 [Windows Installer]
Custom Action Type 51 [Windows Installer]

[Author: Robert Flaming]
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