To Setup Inbound Email Service, check the following link https://www.infallibletechie.com/2012/12/inbound-email-creating-record-using.html Sample Apex Class: Apex Class: global class OrderCreation implements Messaging.InboundEmailHandler { global Messaging.InboundEmailResult handleInboundEmail( Messaging.InboundEmail email, Messaging.InboundEnvelope env ) { ....
assignmentRuleHeader.useDefaultRule should be set to true using Database.DMLOptions to trigger Assignment Rule when the Case is created using Inbound Email Service. Sample Apex Class: global class createCaseInbound implements Messaging.InboundEmailHandler { ....
Sample Code: global class createCaseInbound implements Messaging.InboundEmailHandler { global Messaging.InboundEmailResult handleInboundEmail(Messaging.InboundEmail email, Messaging.InboundEnvelope env) { Messaging.InboundEmailResult result = new Messaging.InboundEmailResult(); String myPlainText= ''; myPlainText = email.plainTextBody; try { Case objCase ....