Plesk includes language packs, the translations of user interface into different languages. If you would like to see the list of supported languages, refer to Plesk localization guide. All the supported languages are installed during the Plesk installation (either clean installation or upgrade), and do not require any additional actions from you to start using them. The number of languages you can use depends on the Plesk license you purchased. Plesk will alert you when you attempt to use more languages than allowed.
To view the interface languages installed in Plesk:
Note: you can make a language unavailable to control panel users. To do this, click an icon . To make a language available to users, click an icon .
To select a new default language for Plesk: