Cannot Install Bootcamp Drivers

Hi, my iMac late 2012, I recently installed Windows 7 x64 Ultimate and installed Bootcamp Drivers 5 so I can get my things working. Suddenly, it fails and cannot do it. It says "This version of Bootcamp is not intended for this computer model.". I got the correct drivers. I have checked my model on Apple's Windows 7 Bootcamp Support and it's correct. My version of the Bootcamp drivers is "5.1.5769". If you have a way to get me in the processs! Also I had to manually go through the Drivers folder and install all the drivers so please help! Thx.