Is it possible?

I'm trying to do this:

var dt = new DocumentType(1244);
var u = new User(0);
var parentId = 1146;
var d = Document.MakeNew("avi creation", dt, u, parentId);

When it comes to "Document.MakeNew", It throws me that error:

Message:Object reference not set to an instance of an object.

at Umbraco.Core.Configuration.UmbracoSettings.GetKey(String key)
at Umbraco.Core.Configuration.UmbracoSettings.get_EnableLogging()
at umbraco.UmbracoSettings.get_EnableLogging()
at umbraco.BusinessLogic.Log.Add(LogTypes type, User user, Int32 nodeId, String comment)
at umbraco.cms.businesslogic.web.Document.MakeNew(String Name, DocumentType dct, User u, Int32 ParentId)

Does anyone know how to solve it? i'm using dlls of umbraco version 4.9.1

Does anyone know if it's possible?

If so can I get an example?