Instructions
Open the "Documents" or "My Documents" folder. This folder can be clicked on easily from the start menu.
Double-click the "Microsoft Games" folder. A list of games distributed by the publisher will be displayed.
Double-click the "Zoo Tycoon 2" folder. The game's saved game files and other miscellaneous files will be shown.
Right-click the "zoo.ini" file. A list of options will appear.
Hover over the "Open with" option and click "Notepad." If the program does not appear in the list, click "Choose default program" and double-click the program from there. The file will be displayed in lines of text.
Insert your cheat code at the bottom of the document. Most of the game's cheats can be inputted by placing them at the bottom of the file, while a few will have you actually editing a line of code. If your cheat requires you to existing lines of code, it will say so in its description. Cheat codes for the game can be located across a variety of cheat code databases, including Cheatbook, Cheat Freak, and eConsultant (see Resources).