The sender simply clicks on the File Share - Add Files button to browse and upload the desired attachments.
Once the recipient gets the email, they click on the yellow Download Files button which directs them to a portal where they have up to 90-days to download and save the attachments transmitted (the availability period for these files can be configured to range between 7 and 90 days using the setting File retrieval link available for download in RPortal).
Note: If an email was sent using the File Share feature, the attached files cannot be recovered from the sent email since the files are linked to a URL, instead of actually being attached to the email. Therefore, the email in the Sent folder contains the email body and a list of attachments sent but not the attached files themselves.
If the sender wishes to re-send those files, they would have to compose a new email and use the File Share feature again.
The following short video explains the various ways you can send large files or attachments through Outlook using the File Share feature (formerly LargeMail) in RMail. It also covers the option to encrypt those attachments and how the recipient will receive them.