So, my ultimate goal is to connect a Firewire 800 device (medical instrument) via thunderbolt. I got my hands on two Apple thunderbolt adapters, first a TB 3 to TB 2, and then a TB 2 to Firewire 800.
When I connect the TB 3 to TB 2, Windows says "Try improving the USB connection" and it links me to this page. Opening the thunderbolt software shows no connected devices. I have the latest drivers that I am aware of, software package version 220.127.116.115. I have BIOS version 1.4.10. I have disabled the thunderbolt security in BIOS and enabled the boot related thunderbolt options.