In order to use Full Disk Encryption on Windows 8 you must use client v4.7.4 or later.  This client includes support for GPT, UEFI and Secure Boot technologies.  These technologies are a requirement of machines supplied by manufacturers that display the Windows 8 certified logo.

Client versions previous to v4.7.4 will function with Windows 8 allowing all features of the product with the exception of Full Disk Encryption which is unable to be performed if the system is using UEFI or GPT.

The DESlock+ client does not support the RT editions of Windows 8.

Full Disk Encryption can be used on tablets running Windows 8 but you will need to connect a USB keyboard in order to enter your FDE user credentials when starting the system.

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How can I tell if my computer is using UEFI and Secure Boot?