CustomUpdates
A Custom Update is a standard update where you can perform "Actions" before and/or after the installation of the main file. For example, you can uninstall an application before installing a new application that will replace the previous one. You can kill a process, delete a file/folder, delete registry keys… Go to "Tools" -> "Create a Custom Update…".
A custom update must return a "return code" at the end. The return code can be static (always the same code) or variable (depend of the result of an action). By default, the custom update will return 0, which generally means "Successfully installed". But you should set the custom update to return the result of an action, especially if your custom update install a MSI or MSP file. To do that, simply select the option "Store the return code into a variable" when setting the "Install MSI file" action. And choose "Content of the variable" at the bottom left of the main window.
