We have used pre-requisites to install external program. It is installed silently regardless if full GUI used for installer. I am facing one issue. Pre-reqs are not installed when I install the installer silently using following command:
I've analyzed your project and log file. Thank you for sending them.
According to your log the features associated with the prerequisites are not scheduled for installation because their install condition is evaluated to false. During the silent installation the install condition of the features is evaluated during "Cost Finalize" action from "Paths Resolution" stage.
I've noticed that your custom action that sets the properties used in the features install conditions is scheduled to run after paths resolution. Instead you should place it before "Paths Resolution" in "Install Execution Stage", ensuring the features install condition is true at the time it is evaluated.