thanks a lot, I just try:
ex.StatusCode: error 401
ex.TwitterDescription: null
ex.TwitterExtensionInfo: "{\"request\":\"\\/1.1\\/statuses\\/update.json?status=hello&trim_user=true\",\"error\":\"Read-only application cannot POST.\"}"
ex.Weberror: {"Error in the remote server: (401) Not authorized."}