HTTP 403 error "Forbidden" on a write request
A POST, PUT, or DELETE REST request returns response code 403 and the response body contains the following text string:
Forbidden
The user attempting the request is not a member of the
administrators group.
Log in to the REST API with a user name that has administrator rights as part of the
administrators group.
The user must be a member of the predefined
administrators group. POST requests to the
login resource fail for members of a user-defined local user group.