How do I make the install4j updater remove files?

Question

Our install4j-based app has a 3rd party library jar called (eg) foobar-1.0.jar

In an updated version, we have replaced the jar with foobar-1.1.jar

The install4j updater adds the new jar, but doesn't remove the old one. So now both are on the classpath. This is making our app crash.

How can I tell the updater to remove a file that no longer should be there?

Answer 1

You can add an "Uninstall previous installation" action to your "Installation" screen.

If there are some files that you do not want to delete during such an update, go to the "Files" step, edit an entry, switch to the "Installation options" step of the wizard and set the "Uninstall policy" to one of the "... but not for update" options.

Answer 2

Here is a screenshot of where and how to add the uninstaller.