Mega Drivers

Hiya,
I have tried loading drivers onto the Mega 2560 multiple times. I have Windows 8. When I select the drivers file to load it says " The third-part INF does not contain digital signature information." What is my problem? Am I selecting the right folder? Right now I am selecting the whole drivers file.
Help is greatly appreciated
1001100111100

Version 1.0.4 has signed drivers for Win 8.
http://arduino.googlecode.com/files/arduino-1.0.4-windows.zip