Virtualization and data execution protection enabled in BIOS...but disabled in OS

I’ve installed Docker for Windows, Version 17.0.6.2 (13194)

I’m running Windows 10 Pro (Build 15063) 64 bit. I have Hyper V installed. I have made sure I have “Virtualisation Technology” and “Execute Disable Bit” enabled in the BIOS.

However, when I check task manager, Virtualisation is disabled and Docker says an error occurred, “Hardware assisted virtualization and data execution protection must be enabled in the BIOS”

My processor (Intel Core i7 920) and motherboard (DFI x58-t3eh6) are pretty old but do support Virtualisation.

I feel like I’m going in circles, does anyone have any thoughts on what I can do to solve this issue?

Happy to try anything to get this to work.