Error: "Response status code was unacceptable: 403"

Problem

The client gets this exception:

Solution

This error occurs when the setting " SkypeShield App use required" on the Admin Portal is disabled.

  1. Go to the Admin Portal under Settings → MDM Integration.
  2. enable SkypeShield App use required to yes and click save.
  3. Restart the SphereShield for SfB Reverse Proxy (Bastion) .
  4. Close SphereShield and Skype for Business app and restart the registration.