After installation, I want to change the system language of the PRTG web interface.
This article applies as of PRTG 24
Change the language of the PRTG web interface
In PRTG
You can change the system language of PRTG in the PRTG web interface: From the main menu, choose Setup | System Administration | User Interface . In section PRTG Web Interface, select your desired Language.
This setting defines the language of the PRTG web interface and the PRTG Administration Tool.
In the PRTG Administration Tool
As an alternative, you can change the language in the PRTG Administration Tool on the PRTG core server system.
Click on the Web Server tab, select the desired system language, and confirm your changes.
A restart of the service is required for the changes to become active.