This article demonstrates how to attach multiple files in CALL object?
By default, in Automic Web Interface, you can add only one attachment to a CALL object.
It is impossible to enter several files in the field AE Attachment (see green box at bottom):
<Please see attached file for image>

For functional reasons, it can happen that you need to add several files to a mail.
For example, some reports automatically generated in a directory of your SAP Agent should be forwarded to the financial team by mail.