Visual Studio Setup Project and Custom Action Usage (Installer Class)

I have an installer, an MSI file, when executed interactively (by an end user), it installs just fine. Specicially, the Custom Action I added to the MSI via an Installer class, executes as part of the users installation.

However if I execute the installation, via Scheduling a Task on Windows 7, as the SYSTEM user account, th开发者_JS百科e MSI seems to install, but it looks like my Custom Action does not get fired. I get no errors and the Scheduled Tasks says the installation was successfull.

Does anyone know why or how a Custom Action would be skipped and not executed which seems to be the situation.

Thanks