USPasp Programmer / Working on Win XP but not on Windows 8

Hi,

following Setup:

I have a Laptop running with Windows xp that I use for programming. It has the USPasp Drivers installed and I can Programm my atmega328 Chips with this. Also burning the bootloader is not a Problem. I downloaded the Drivers from the Website (something with fischl.de)

No I have a new tablet running with Windows 8. I had to disable the unsigned Driver protection to be able to install the Drivers from "fischl.de" If I try to burn the bootloader I get a Problem "cannot set sck clock".

So the only difference is the Operation System. Is there something I have to fix when using Windows 8?

Thanks