Why does Outlook Mail Client (On Mac or Windows) always need to archive all mails on local hard disk? It would be good to control how much of mail should be stored on the disk while the rest can be moved to Storage (linked to OneDrive or any other such Cloud Storage like Box etc). This way, it would be easier to offload the performance of the Server and improve the Cloud Storage market. I'd prefer a seamless integration with OneDrive than any other cloud storage provider. Also, it can increase the Cloud Storage Footprint. Ability to view personal mail (irrespective of whether the Mail account being Active/Not) and selective downloads of important mails to local hard disk via client. This way the flexibility around efficient usage of hard disk is improved and people would flock more to Outlook than GMail or others.