Visual Basic Installer

We are using the visual basic installer to create installer modules for our applications (a setup.exe loads the msi file etc.). When a new version is released, the user runs the setup.exe file and the newest version is installed on their PC. The problem is that the old version still shows up in the control panel (they would need to manually remove it throught the control panel). After 5 new updates, they have 5 'copies' in the control panel list. How can the visual studio installer be used to first uninstall the past version and then install the newest version. Does anybody know of any good articles that explain how the installer works or what the different setting do ? I looked through the Microsoft site but couldn't find anything.

Thanks
Chris

What you should do is detect if the old version is installed and force an uninstall.