Adprep detected that the supplied or default user is not a member of the following group: Schema Admins Group. Status/Consequence ...

Adprep detected that the supplied or default user is not a member of the following group: Schema Admins Group.
[Status/Consequence]
Adprep has stopped without making changes.
[User Action]
Verify the user is a member of Enterprise Admins group and Schema Admins group.