http status codes- 422 unprocessable entity

422 unprocessable entity http status means that due to sematic errors , server is unable to process the request although xml request body format is correct and varifiable but due to above semantic error . server is unable to process it.
Server may respond to you by saying 415 unsupported media type or 400 bad request ; it may depend.you are reading about http status codes- 422 unprocessable entity.