Not allowed to open windows

Shanty is a new employee in a company. As a new employee, she should obey all the rules in the company. One day, Shanty confused when she was told by her boss to open Microsoft Excel. After an hour had passed since she was ordered to open that application in Microfot Windows.
Because she became more confuse, then she decided to open DOS. Seeing this, the boss get angry because of her. “Hey! I asked you to open Microfot Excel, but why you opened DOS??” the boss said. Then Shanty answered “Boss, i do not want to disobey the rules” she answered. Then the boss get confuded and he asked “What rules?”
With poiting a note on a wall, Shanty read it. “This room is equipped with air conditioner, please do not open windows, How can i open Microsoft excel if i am not allowed to open Windows?”