When creating a user(s) via the Active Roles Management Shell, you may encounter the following error:
Administrative Policy returned an error.
Exchange Server-related operation failed.
A property that is required to perform this operation is not specified. Missing property: mailNickname
This is a product defect (TF00649815). It is a conflict between the 'Generates user logon name (pre-Windows 2000)' and 'Generates e-mail alias' policies when nested on the same provisioning policy.
Split the 'Generates user logon name (pre-Windows 2000)' and 'Generates e-mail alias' policies, so they are on separate provisioning policies.
To be corrected in the next maintenance release (Patch 5), expected to be released around Mid-2017.