> ## Documentation Index > Fetch the complete documentation index at: https://insightsoftware-preview.mintlify.site/llms.txt > Use this file to discover all available pages before exploring further. # Clean Installation And Upgrade Differences An upgrade of Composer means that you are upgrading from an earlier version of Composer to a newer version of Composer. This includes uninstalling the previous version and installing a later version. To learn more about upgrades, see Upgrading the Composer Server. A clean installation of Composer means that you are installing a new version of Composer from scratch. The Composer metadata is empty and contains no information. This either means that the PostgreSQL is a fresh install as well or that the zoomdata database is empty. A supported upgrade of Composer allows users to continue working in an existing Composer environment while a clean installation of Composer is completely new. For clean installation instructions, see [Install Composer](/logi-symphony/composer/v25/licensing/install-composer). The main difference between an upgrade and clean installation of Composer is whether or not the PostgreSQL is from an existing Composer installation or is new and empty.