You should close the digital signature when you are using Win8 or Win8.1.
You should save these files which you are editing before installing driver with window8，because there will several power off during operating.
- Press “Windows Key” +”R”
- Enter shutdown.exe /r /o /f /t 00
- Click the “OK” button.
- System will restart to a “Choose an option” screen
- Select “Troubleshoot” from “Choose an option” screen
- Select “Advanced options” from “Troubleshoot” screen
- Select “Windows Startup Settings” from “Advanced options” screen
- Click “Restart” button
- System will restart to “Advanced Boot Options” screen
- Select “Disable Driver Signature Enforcement”
- Once the system starts, you can install the driver