Content Repository to check is U1 which came from Document category “Z_IXOS_U1”. Although the connection test in your screenshot is successful, HTTP Error 401 still happens in below mail. Some of the research we’ve done was to check the settings of the content repository in the CSADMIN for the security and certificates. Sending the mail is not really a problem as what you tested before but it is actually the attachment functionality which does not work and causing the issue. This issue also happens in DS1 wherein you can’t attach an excel file in the SAP mail. Unfortunately we can’t debug anymore as the error occurs from the RFC call specified by Prashant below. Hopefully this helps. Thanks!