After pushing profile some iPhones become unusable
We are managing up to 100 iPhones an iPads with the Profile Manager.
After some changes of the device profile, the profile was pushed automatically to all devices. Some iPhones became unusable. The Exchange-Connector no longer works. About 90% works fine.
What went wrong ?
iPhone: 5 and SE
iOS 10.X.X to 11.2.6
iPhone SE, iOS 11.2.6