'AllowAnonymous' could not be found
问题 Everything worked fine until I installed (Package Manager Console) the postal package, then uninstalled and installed an older version. Now I get an error where it previously was not. Error: The type or namespace name 'AllowAnonymous' could not be found (are you missing a using directive or an assembly reference?) Who knows how to fix this? 回答1: Probably you are missing the reference to System.Web.Http assembly in your project? So you need to: Add the reference to System.Web.Http ; Add using