David wants to know about securely sending attachments to clients with Exchange. Leo says that he prefers to send a link to the file saved in the cloud. It's secure, HIPPA compliant, and much easier than sending attachments, which can be notoriously insecure. Leo recommends ShareFile from Citrix. David can also set it to expire, use a password, and other security guarantees. It makes email smaller and more secure.
Free options include FireFox Send by Firefox, where David can send files up to 2.5gb.