When we build a Setup with VS 2010, we have the ability to choose DetectNewerInstalledVersion=True and RemovePreviousVersions=True. So, we can install over an existing setup. Otherwise, we have to remove the previous setup before installing the new setup. When we remove the previous setup, this doesn't create any problem as everything is removed before installing the new version. But, when we install over an existing version, if something goes wrong during the setup, this creates a mess. So, basically, we cannot any longer go in Add\Remove programs to remove the previous setup. We cannot run the new setup. The only way is to go in the registry and remove all traces of our setup. This is something we cannot ask the user.
So, basically, I am curious, is there anyone overwriting an existing setup or you always create a setup that will force the user to remove the previous version?