Email-to-Case is a solution that can meet the requirement of Universal Containers' email policy that requires all email traffic to remain within its firewall. Email-to-Case allows administrators to set up an email service that runs on their own servers and converts email messages into cases in Salesforce. Email-to-Case does not require any email messages to be sent or received outside the company's firewall, unlike On-Demand Email- to-Case. Verified References: : https://help.salesforce.com/s/articleView?id=sf.case_email_overview.
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