Below process will help you to pass username and password in outbound web service from Siebel. Follow below steps: 1. Open Siebel Application login with admin user go to site map and search Web Services. 2. Go to Outbound Web Service and query for your desired web service for which you want to pass username and password. 3. Go to Operations Applet and select "Username/Password - clear text" Authentication Type for desired method. 4. Clear Cache (on Outbound Web Services Applet) 5. Go to workflow and on business service step through which you are calling outbound web service. 6. Add "siebel_transport_header:Authorization" as Input Argument with Type "Literal". 7. Convert username and password in Base64 with below format: username:password 8. Add converted credentials against "siebel_transport_header:Authorization" in Value as below: Basic dXNlcm5hbWU6cGFzc3dvcmQ= 9. Save, Deploy and Test.