Why doesn't SuperSU ask to disable KNOX after rooting (Galaxy S5)?

[AC Question]

SuperSU does not ask to disable KNOX after rooting. Galaxy S5

So today I downloaded the latest supersu in my samsung galaxy s5 with TWRP recovery. When I first opened the SuperSU app, nothing happened. It did not ask to disable KNOX. Then I downloaded some apps that needed root. SuperSU had granted permission to the app, but the app wouldn't say it did. It said to get root.

What is causing this?

 

[itguyjax8430]

Re: SuperSU does not ask to disable KNOX after rooting. Galaxy S5

So today I downloaded the latest supersu in my samsung galaxy s5 with TWRP recovery. When I first opened the SuperSU app, nothing happened. It did not ask to disable KNOX. Then I downloaded some apps that needed root. SuperSU had granted permission to the app, but the app wouldn't say it did. It said to get root.

What is causing this?

Welcome to Android Central!

Try rebooting in to recovery and clearing the cache partition. Boot back up and open SuperSu and see if that fixes it.

 

[JimTheGlawsFan]

Just tried wiping the cache partition and that didn't work for me either.
I'm sure I was able to disable KNOX the first time I rooted, but can't get it to play ball this time round. Annoying.