When I download the .mobileconfig for a device pool, email it to an iOS and try to open it, the installation fails.
Tapping the install button triggers a confirmation prompt warning the installation will change setting on the phone. Tapping "Install Now" gives way to a a prompt saying "Profile Installation Failed - Invalid Profile"
I'm quite certain that this worked at least once before. I've tried in both an iPhone and a completely virgin iPad (i.e., that was never under MDM before).
How can I understand why this is happening? I imagine that a lot of things can cause this behaviour, so can we go about debugging this?
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