IOS devices cannot register device to the wireless network

[joram_laureys]

We have a zonedirector 1200 (9.12.3.0 build 28) and ruckus zoneflex 600 AP's. We want the teacher in our school to register their device with zero-it. This works well for all android and windows devices, but for most IOS devices this does not work. When they get to the 'zero-it portal site' and click register device, nothing happens. When we try to 'bypass' the portal site by going to wifi.ourdomain.com/activate, they can enter the username and password. But again nothing happens. Any ideas ? 

[michael_brado]

CNA Bypass?

[joram_laureys]

Does not help, still nothing happens when we click on register device. (clicking on guest acces works)

[joram_laureys]

OK, found the problem.
The newest version of ios (10.2.1) blocked our certificate. We reseted the certificate to default and everything works again.

[rafael_lopez_c8]

Where did you reset the certificate? At the ZD controller or at the IOS devices?
What kind of certificate are you using?