I thought I knew the answer to this but just can't get it to work properly...
I had an installation procedure created within Visual Studio 2010 but decided to re-write it using InstallShield 2010 as I don't like the interface to the VS solution.
I have copied over the Product and Upgrade codes from the Visual Studio Installer and have set the same product name. When I run the installation built in InstallShield I correctly get an error saying that the product is already installed - just what I wanted.
I now change the version number in InstallShield and re-generate the PRODUCT CODE. rebuild the installation and run it again. What happens is that I get both the old and new versions of my application installed. I expected the old version to be upgraded as the UPGRADE CODE is the same in both installations.
Any thoughts on what I am missing? I need my new Installation to perform an upgrade