You can only download a valid installer.php file by first creating a "Package" within the WordPress dashboard.
To move your site, you must upload both the installer.php and the matching archive file to the root directory of your new server. How to migrate your WordPress with the Duplicator plugin duplicator installer.php download
: Navigate to Duplicator > Backups (or Packages) and click Create New . You can only download a valid installer
: The plugin will scan your site for potential issues. Once complete, click Build . : The plugin will scan your site for potential issues
: If you cannot access the dashboard, you can find existing installer files on your server via an FTP client like FileZilla in the /wp-content/backups-dup-lite/ directory. Using installer.php for Migration
For WordPress users, the file is the essential "engine" that powers website migrations and restorations. It is a standalone script generated by the Duplicator plugin to automate the complex process of unpacking a site’s files and reconfiguring its database on a new server. How to Download Duplicator installer.php
: After the build finishes, you will see buttons to download two critical files: the Archive (a .zip or .daf file containing your site data) and the Installer ( installer.php ).