If you are upgrading from the same major version (such as upgrade from Version 3.0 to Version 3.1), do not uninstall the former version. During installation, do not change the default installation folder. The old version will be overwritten automatically. All your former data will be reserved. If you are upgrading from different major version (such as upgrade from Version 2.0 to Version 3.0, follow the upgrading guide to upgrade.