Disclosed are various embodiments for facilitating the sharing of files or documents on behalf of a sending user to a recipient user. A secured file is transmitted to a recipient user via a primary communication identifier. A security key that can be utilized to decrypt or unlock the file is transmitted to a secondary communication identifier, which can be automatically identified. In this way, security of the file can be maintained in the event that one of the communications channels corresponding to the primary communication identifier or secondary communication identifier is compromised.