I have a S4 LTE International GT I9505 and i rooted it and installed a custom rom, but now i came back to official firmware.
So when click on wifi it simply doens't turn on and a notification appears:
" SECURITY NOTIFICATION - Your device's security blocked a non permitted action. It isn't necessary any action" with a grey shield icon.
If someone help me i will be grateful.
EDIT: It seems that i cant choose another unlock option too.