Prevent Case Creation for Bounced or Out-of-Office Emails

How It Works

First, configure a unique Case Origin value (for example, Support Email) specifically for cases created by Email-to-Case. This allows the trigger to identify which cases originated from an email and which originated from other channels. The Apex trigger then inspects the Subject field of incoming cases to detect OOO patterns or bounce notifications and takes the appropriate action.

Example Code

The following Apex trigger runs on before insert for the Case object. It detects Email-to-Case cases based on the Origin field and provides a placeholder for your custom logic to block or flag them. Customize the logic inside the if block to match your organizational requirements:

trigger manageEmailCases on Case (before insert) {
    for (Case thisCase : trigger.new) {
        if (thisCase.Origin == 'Support Email') {
            /* Add your logic here.
            Example: block cases with OOO subjects
            if (thisCase.Subject.contains('OOO')) {
                thisCase.addError('Not saving — Out of Office email');
            }
            */
        }
    }
}

What Logic to Add

Customize the logic inside the if block to match your organization's requirements. Common approaches include:

• Checking for keywords like OOO, Out of Office, Bounced, or Undeliverable in the Subject field.
• Using thisCase.addError() to block the case from being inserted.
• Setting a custom field flag (for example, Needs_Review__c = true) to mark the case for manual triage instead of blocking insertion.

Considerations

Hard-coding known Origins or Subjects is one approach, but you also want to avoid accidentally blocking legitimate cases with poorly written logic. Consider making your detection patterns configurable using Custom Metadata Types or Custom Labels so they can be updated without redeploying code. Adjust the logic to account for emails in different languages or variations of Out-of-Office text. It is often safer to flag cases for review rather than block them entirely, especially when you first deploy the trigger.