mportant information for x64-based operating systems
Ensure that you have updated and digitally signed kernel-mode drivers for Windows Server 8 Beta
If you install a Plug and Play device, you may receive a warning if the driver is not digitally signed. If you install an application that contains a driver that is not digitally signed, you will not receive an error during Setup. In both cases, Windows Server 2012 will not load the unsigned driver.
If you are not sure whether the driver is digitally signed, or if you are unable to boot into your computer after the installation, use the following procedure to disable the driver signature requirement. This procedure enables your computer to start correctly, and the unsigned driver will load successfully.
To disable the signature requirement for the current boot process:
Restart the computer and during startup, press F8.
Select Advanced Boot Options.
Select Disable Driver Signature Enforcement.
Boot into Windows® and uninstall the unsigned driver.