How to prevent SAP from sending External Mails

Whether you are doing a SAP Upgrade Project, or working on an Issue which involves sending external mails, this setting could prevent accidentally sending out E-mails.

1) Go to SCOT
2) Expand INT
3) Double Click on SMTP
4) Add a # in the Mail Host field. E.g. before = 10.2.1.1, after = #10.2.1.1
5) Uncheck Node in Use