Best Answer overlord , 31 August 2015 - 20:00
ok so I decided to go back and poke at this a little more. I had cut and paste the setup for ISPREVENTDOWNGRADE from the official documentation for installshield found here:
http://helpnet.flexe...gDowngrades.htm which has the following information I used.
In the Minimum Version setting, specify the product version that you are using for your current project. As an alternative, you can enter the following string in this setting: ***ALL_VERSION***
which should actually be ALL_VERSIONS plural. When I caught the mistake and added one freaking s preventdowngrade started working the way it was supposed to.Go to the full post