Email-to-Case and On-Demand Email-to-Case Overview
Email-to-Case and On-Demand Email-to-Case help your company efficiently resolve customer inquiries via email. Salesforce automatically creates cases and auto-populates case fields when customers send messages to email addresses you specify.
Email-to-Case and On-Demand Email-to-Case are available in: Professional, Enterprise, Performance, Unlimited, and Developer Editions.
These are few differences between Email-to-Case and On-Demand Email-to-Case.
Email-to-Case requires downloading the Email-to-Case agent. This lets you keep all email traffic within your network’s firewall and accept emails larger than 25 MB. You must install this agent on your local machine before Salesforce can process your company’s support emails.
Unlike Email-to-Case, On-Demand Email-to-Case uses Apex email services to convert email to cases, without requiring you to download and install an agent behind your network's firewall. Use On-Demand Email-to-Case if you’re not concerned about keeping email traffic within your firewall, and you don’t need to accept attachments larger than 25 MB from customers.