Error enabling two-factor authentication

I recently updated my iPad to iOS11 beta, which prompted all my apple devices to enable 2FA. Worked fine on my MBP and iPhone, but my Hackintosh is having problems.

Here is the settings screen: http://i.imgur.com/5Tlb7II.png

Here is the error I get: http://imgur.com/VyHAmbA

Validated my firewall & web filtering isn't stopping it - So must be something with my Hack?

Anyone else com across this issue before?