Archiving email from your Primary Inbox or Exchange mailbox in Outlook can make a huge difference in performance and stability. But remember that once you move your messages into an Archive, you need to be sure you BACKUP those archive files…once the message leaves the Inbox, that YourArchive.pst file is the ONLY PLACE that message exists.

You won’t have access to those messages in your Outlook Inbox, web mail, or any connected mobile device, so be sure to use the date range feature to optimize the process for your own needs.

This article describes performing the archive process manually, but you can also configure the Auto-Archive feature to make it a no-brainer!

Archive items manually – Outlook.

Archive items manually - Outlook