We recently moved from a Visual Studio setup msi-based installer to Inno Setup but we're having issues with upgrading existing installs using this new installer. I know that the upgrade code remains static even as the product code changes every update, so I initially tried to set that as the AppId in the Inno Setup project, but that doesn't work. I then tried a number of other guid's none of which work.
Is there a way to properly upgrade an msi install with an Inno Setup installer?
Best Answer
No, I don't think so - InnoSetup is expressly NOT an MSI-based installer.
You will need to first properly uninstall your old MSI-based installation using e.g. msiexec /X (product-code or MSI file name), and then you can install the new stuff using InnoSetup.