Driver installs haven't changed since Windows 2000 and every printer installs the same way in most regards. If you have an issue you need to explain it fully, not state that "it doesn't work", that is a useless statement and helps nobody to understand your issue.
Since it is a Global driver, all you should need to do is right-click the unspecified device, go to Properties and select Driver.
Choose Update driver and point it at whatever driver is in C:\Xerox
You can simply check here for the config, or follow the other guys post.
THANK YOU FOR YOUR ANSWER, but i still can not install, i tried with 2 links, but the printer don´t install. are there some especial step to follow?, when i connect the printer to the computer this appear, But on unspecified devices, and when install that links (the links you sent me) this appear like a new printer, but my printer continues like unspecified devices
Xerox Global Postscript driver
HI
I need help to install my xerox phaser 3121 on win 8, i can not find the drivers, i had change my computer recently and i need install my printer, i do not want change my printer
please help me thank you