Overview
The S4S EXM web service is able to be configured to use client-side certificates for the callouts from Salesforce.
Create Certificate in Salesforce
To create a certificate in Salesforce
Setup » Administer » Security Controls » Certificate and Key Management (Salesforce Classic)
Setup » Settings » Security » Certificate and Key Management (Lightning)
Click Create Self-Signed Certificate
Enter the name for the certificate
Click Save
Click Download Certificate. This will download the certificate as a crt file
Configure IIS to Use Salesforce Certificate
To install the certificate onto the IIS server
Right-click on the crt file and select Install Certificate
Select Local Machine and click Next
Select Place all certificates in the following store, select Trusted Root Certificate Authorities and click Next
Click Finish
Configure S4S EXM Package
The package needs to be configured to use the certificate.
Setup » Build » Develop » Custom Settings (Salesforce Classic)
Setup » Platform Tools » Custom Code » Custom Settings (Lightning)
Click Manage in front of S4S LBPlus Settings
Enter the certificate name into the Web Service API Key field in the S4SEXM package custom settings
Click Save
Next Step
Congratulations, you have finished installing this module.