Problem with my Arduino 2560 R3 [Solved]

Hello everybody!
I have a problem with my Arduino 2560 R3 card. I started with Arduino yesterday. I use Windows 8. I did the tutorial for beginers of Arduino. But I couldn’t do anything. Then I saw that the controller installed when I connected the card with my PC appear how “Unknown controller”.
For this reason I have problems. Then I tried to update the driver but I couldn’t do it, because my Pc doesn’t recognize anything. I think that this occurs because the controller is unknown and then the PC doesn’t know to do.

Can anybody help me? I don’t understand anything. What is the reason of the message “Unknown controller”? How can I solve it?
Thank you!!

Do you have Arduino IDE installed? With drivers?