Windows 10 Windows 10 mail shows wrong display name when sending messages from second or more accounts

The Win10 "Mail and Calendar" app does not support more than one displayname attribute; sent messages are attributed with the same displayname attribute as the initial (iow, "first") messaging account configured in the "Mail and Calendar" app. This is neither a design oversite nor a bug. Indeed, when configuring multiple messaging accounts within the "Mail and Calendar" app, the user is prompted to enter a displayname attribute only during the set up of the initial (iow, "first") messaging account, and the user is not prompted again upon the set up of subsequent messaging accounts within the app.

If it is desirable for sent messages to be attributed with a displayname other than that of the initial messaging account, the "work around" is to enter a space character into the "Send messages as" (or equivalent for the most recent revision of the app ) field. This forces the "Mail and Calendar" app to attribute the full email address (ex: "acctname@domain.etc") to all sent messages from every messaging account configured within the app. Alternatively, the user should install a third-party messaging app that provides the functionality they desire.