File too large to email? File too sensitive to email? We have a solution for those problems. Link Sharing in OneDrive. Using the attached instructions, you will be able to create, and share, a link to a file (or folder) to an outside user. You can create a password for the link and/or put an expiration date for the link. After you copy and paste the link into an email, the person will not need to log into Office 365 to access the file or folder. You would only need to phone them with the password (if you created a password) or the link would expire the next day (or whatever date you choose).
Warning, if emailing sensitive data, you should use both the password and an expiration date in the event the link is forwarded to someone else or accessed months later.