OTG Installer - PHP Fatal error: Uncaught Error: Class "WP_Installer" not found in...

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Assisted by: Bobby.

Author	Posts
April 2, 2026 at 7:44 pm #17946942
Milan Media	Hi there. We are getting this PHP Fatal error when trying to install the latest version of OTGS Installer on both staging and production sites: Uncaught Error: Class "WP_Installer" not found in /var/www/html/wp-content/plugins/otgs-installer-plugin/vendor/otgs/installer/includes/functions-core.php:6 Manually updating each plugin does not work as well. Thank you for your assistance!
April 3, 2026 at 5:52 am #17947218
Bobby WPML Supporter since 04/2015 Languages: English (English ) Timezone: America/Los_Angeles (GMT-07:00)	Hi there, OTGS Installer is meant to be used only on sites that have never deployed WPML before. Once WPML has been installed and activated OTGS installer will not be able to be activated. In order to update the products go to Plugins->Add new->Commercial tab and check for updates, however, if your versions are quite behind it is best to do this manually. You mentioned that you experience issues when manually doing this, please share with me what happens during manual attemps. NOTE: This needs to happen only once afterwards you can resume auto updates.

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