launch a second installer from a custom action installer class

Question

I have a WinForms application that requires some configuration which I do at install time using a custom installer.

We have also created a web service which is installed from a separate msi.

I'd like to have a radio button selection allowing the installer to run just the client installer or the client and service installer.

Creating the custom action for the radio button is simple enough (Example here)

So to my questions:

• Should I include the web service files into the client installer or execute the web service msi?

• Some of the parameters used by the client install are required in the web install. If I launch the separate msi, can I pass these values
  across without the user having to enter the data twice?

• If I include the web service, how do I go about combining client and web installations?

EDIT: Things I've tried:

I have tried creating a web installer and creating the directory structure for the client executable but this then causes a permissions error (probably because I'm installing to the Program Files folder). I suspect this will be the same issue if I try a client installer and manually create the directory structure under inetpub for the web service.

If I include the built output from the web service installer, I can not access it from the Custom Actions Editor screen and therefore can't apply the conditional launch.

It's starting to look like I will need to extend the custom installer class that I currently use to launch the msi as a shell command but this doesn't seem like the correct way to do things.

Answer 1

It's not possible. Windows Installer implements a mutex that prevents this. The only way you'll automate the installation of both of those MSI's is through the use of a bootstrapper / chainer.