Use XML Search predefined support from Advanced Installer to retrieve elements from XML files.
The Creating an XML Search tutorial will guide you step by step in the process of creating a valid and working XML custom search. This type of search operation can be useful during the installation, upgrade or removal process in order to copy or delete certain files or features based on the content of an XML file.
Check the attached sample project where the user is asked to enter some information. The information are stored in an XML file and retrieved during an upgrade.
After you build and installed the sample app, you can go in the Product Details page and increase the Product version (when prompted, please select the major upgrade option). Rebuild the package and launch to install it. Notice that the fields already contains the previous entered values.
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