There are two ways to extract messages from the archive.
First, you can forward one or more messages to an email address that you specify. This can be done from the message search results page, the tagged messages listing page, or the message details page. The original message will be forwarded (as an attachment) to the address you specify.
Second, there is an Export tool that allows a domain administrator to export a copy of archived emails to PST or zipped EML format. Note that only domain administrators outside of Europe have the ability to export this data, due to privacy regulations. Messages can be defined for the export based on the associated mailbox(es), date range, retention policy, and/or message tag.
When the export process is complete, the resulting export file(s) will be available for download via HTTPS. The export files will be available for one week, after which the export files will be removed from the download location.