Once you have completed the steps described in the section Before Upgrading Plesk, you can proceed directly to the Plesk upgrade.
If you use Plesk 10 or later, you can perform the upgrade directly from Plesk. Details on how to do this are provided later in this section.
If you want to upgrade from earlier Plesk versions, use the Plesk Installer utility. The Plesk Installer utility is available for download from http://installer.plesk.com/plesk-installer (for Linux) and http://autoinstall-win.plesk.com/plesk-installer.exe (for Windows).
Plesk Installer can be used either via a browser-based user interface or command line. Learn more in the corresponding sections below.
Some Plesk licenses do not grant permission to perform complex upgrades (upgrades that change a major version number: for example, from 10.3.1 to 10.4.0). On attempting to perform such an upgrade, Plesk will warn you about license limitations. Nevertheless, you will still be able to perform the upgrade. When it is finished, you will need to obtain and install a license key for the new Plesk version. For more information about installing a license key after upgrade, refer to the section Installing a License Key.