Cannot create StorageItem in Outlook Add-In
问题 I'm trying to run this code: this.storage = Application.Session.GetDefaultFolder(Outlook.OlDefaultFolders.olFolderContacts) .GetStorage("ws_up_storage", Outlook.OlStorageIdentifierType.olIdentifyByMessageClass); It runs perfectly well on some machines, but on others it throws this exception: I also tried other folder names, like olFolderInbox , olFolderCalendar . I've looked at Microsoft docs for this, and it says this error is to be expected if the folder is one of the following: The folder