This is the 2639th most frequent Russian word.
установлен
"Installed" or "established."
Here, 'установлено' means 'installed' and refers to the action of setting up software.
Программное обеспечение успешно установлено на ваш компьютер.
The software has been successfully installed on your computer.
In this sentence, 'установлен' means 'installed' referring to placing or putting up a physical object.
На улице установлен новый светофор.
A new traffic light has been installed on the street.
Here, 'установлено' means 'established' and is used to refer to confirming or proving something.