I have a Dell Inspiron 14Z 5423 and upon booting up, it says "Intel Anti-Theft system lock due to Platform Attack Detected" It then asks me to enter either
1 - User password
2 - Server Token Password
Intel Anti-Theft Technology is a technology that provides an added level of hardware-based security to protect a laptop and its data if it is lost or stolen. Intel Anti-Theft Technology (Intel AT) is designed to deter theft. Check all the technical resources here.
Let me know if you installed any antitheft software on your computer. Also provide the screen shot of the message to assist you further.