When you try to create a configuration item for a mobile device in Configuration Manager Current Branch, you encounter a "System.InvalidOperationException" error.
This issue occurs if the user who's assigned a custom security role doesn't have read permissions for the Custom Configuration Setting role.
To work around is issue, assign the user read permissions for Custom Configuration Setting.
Article ID: 3205796 - Last Review: 2017 api. 26 - Revision: 2
Microsoft System Center 2012 R2 Configuration Manager