Why does IA always force SQLExpress reinstall?

[Steve]

When I am testing my installation, I notice the following strange behavior:

Assuming that I have previously run IA and installed SQLExpress, when I rerun the setup again it appears to want to uninstall/reinstall SQL Express. I don't think that it is actually running the SQL installation, however the dialogs seem to indicate that it found an exsiting SQL installation is going to uninstall and then reinstall SQL.
The desired behaviour that I seek is to have IA detect that SQL Express is already installed on the system and then just simply skip the SQL portion of the install and proceed to the next step in the installation which is to create a DB and associated directory structure.

There does not appear to be a simple way to set this behavior (perhaps it is just not as simple as I think it should be!)

Thanks in advance for your words of wisdom...
Steve

[MichaelNesmith]

It is very simple. If you click Options in the Application Runtimes view on the SQL Express runtime, you get two dialogs. The first lets you configure the instance that your setup will check for (and skip installation if already found). The second lets you install your own custom instance. As long as you configure both these properly, you will never get prompted for reinstalls.

The Application Runtimes view lets you install an exact instance of SQL Server - its very versatile.