One embodiment of the present invention provides a system that replaces an attachment to an email message with a reference to a location where the attachment is stored. Upon receiving the email message, the system examines the email message to determine if the email message includes an attachment. If the email message includes the attachment, the system stores the attachment at a location on a communication network from which the attachment can be retrieved. The system also modifies the email message by replacing the attachment with a reference specifying the location of the attachment, and sends the modified email message to a recipient of the email message. In one embodiment of the present invention, the recipient receives the modified email message and uses the reference specifying the location of the attachment to retrieve the attachment across the communication network.