Login to your Salesforce org where the package is installed.
Note: We will be creating a Public site to receive all the web hooks for an Incoming SMS. Since it will be an external User, Please make sure that the external profiles does not have access to any Object or Field permissions.
Click on the Gear icon and Go to Setup.
Search for Custom Setting in Quick Find Box.
Click on Manage of “SMS Credentials”.
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FIND {0} IN ALL FIELDS RETURNING Contact(Name, Id ORDER BY LASTMODIFIEDDATE DESC LIMIT 1) LIMIT 10
(Change Object Name in Query as per requirement)
Now, Go to Custom Settings and Click on Manage of “Features Entitlement“.
Mark the checkbox true for SMS and eFax.
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Enter the details as shown in below picture.
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Click Save.
Congratulations! You have successfully installed the Application.