An electronic mail message sent from a sender device is received by an email server. The electronic mail message includes an attachment holder block including an authentication token and an address of an attachment stored at a remote server. The authentication token is transmitted to the remote server to login to the remote server to access the attachment. The attachment is retrieved from the remote server using the address of the attachment. The attachment is attached to the electronic mail message by replacing the attachment holder block with the attachment. The electronic mail message including the attachment is transmitted to a recipient.