Design the workflow. Add new Business Process step on workflow canvas. Add below Business Service Name and Method. Business Service Name: Outbound Communications Manager Business Service Method: SendMessage Now go to " Multi Value Property Window " and Input Arguments and set the arguments as below. AttachFileList > Attachment File path (C:\Siebel\xx.0.0.0.0\ses\siebsrvr\temp\S-WEB-APP_8364_9620_0_Attachment Name.pdf) CommProfile > Communication Profile Name through which Siebel will send the Email MsgBody > Email Body MsgSubject > Email Subject MsgToList > Destination Email (t@t.com; a@a.com) Save the workflow deploy and test. If you need to add attachment from Siebel Contact, Service Request or Case attachment please check the below article: How to get Siebel attachment as file in Workflow If you don't know how to configure or find the working " CommProfile " parameter value please check the below article: Setting up Communication Profil...