Default Fastboot problem Windows 8.1

Hi,

I recently upgraded to Windows 8.1.
It does not recognize the fastboot mode in my Nexus One.

When the phone is connected in fastboot mode (bootloader), Windows gives the prompt 'The last USB device you connected to your computer malfunctioned and Windows does not recognize it.'

Is there a problem with my phone?
What can be done to rectify this?
What fastboot drivers would be required to be installed?

Thanks in advance.