How to make a device with unsigned driver work?

Windows cannot verify the digital signature for the drivers required for this device. A recent hardware or software change might have installed a file that is signed incorrectly or damaged, or that might be malicious software from an unknown source. (Code 52) Recently when I reinstall my Win7 64x system on my PC, I had difficulty of install my TEAC UD503 DAC on it through the USB port. No matter…