How to make InstallShield uninstall previous versions?

Question

I've followed the instructions outlined here, but it doesn't work exactly as I need.:

How to get InstallShield LE to uninstall the existing installation automatically? (apparently this has worked for other people, so it's worth having a look. If it does the trick, be sure upvote @JYelton's answer)

The result of these instructions are that I can install the application without having to uninstall, but now there are 2 separate instances of the application in my Add or Remove Programs window. It doesn't actually uninstall the previous version, it just installs the new version application along-side the previous one.

How can I make InstallShield uninstall previous versions of the application?

Piddling

Answer 1

Configure the new project to remove the old one by using the Upgrade Paths view: Add a New Upgrade Path, and browse to your previous .msi file to ensure it uses the right Upgrade Code. Then tweak the settings that appear, if necessary; typically they should be correct.

Minoan

How does one do this with a VSTO project? There seems to be no installshield configuration options in the publish tab of the add-in project. – Oidium

If I understand well if for example you are at the 3rd version of an app and you have two previous versions then you would have two upgrade paths defined. One with the first version of the msi and one with the second version of the msi. Each time you create a new version you add an upgrade path of the previous version. You don't have just one upgrade path with the most recent previous version. Is this correct? – Offen

Even if the Upgrade Code is correct (same as last msi's) it won't solve the problem; need to change the Product Code too. – Batha