Step 1 - Add a Role for the Case Team Members. Navigate to Setup > Customize > Cases > Case Teams > Case Team Roles > New. We recommend the role "CCed on Email" to help distinguish that the new Case Team Member was originally CCed on the inbound email.
 

Step 2 - Case Teams must be enabled within Email to Case Premium's Inbound Configuration Settings. Navigate to the Email to Case Premium App > Inbound Tab > Additional Recipients > Enable Auto Add Case Team Members. From the Team Member Role for Auto Add picklist, select the Case Team Member Role created in Step 1. At this point, any existing Contacts or Users CCed on an email can be added to a Case Team and receive an auto-response, but if you would like to include foreign email addresses, you must also enable Auto Add New Contacts.

 

Step 3 - Create a new Workflow Rule that fires only on case creation. The criteria should include (and can exclusively be) Subject does not contain [Email Loop Protection] to support email loop protection.
 

Step 4 - Create a new Email Alert. Select your template, preferably one of the Email to Case Premium Auto-Response templates as they contain the proper Thread Id already.  From the Search picklist, choose Email Field and select either the Contact Email or Web Email field. Also from the picklist, select Case Team and add the Case Team Role created in Step 1.  At the bottom, select the appropriate From address for the email. Save.
 

Step 5 - Click Done then Activate your new rule.
 

Note: Make sure to uncheck "Use Active Auto-response Rule" on the Email to Case Premium Inbound Configuration screen AND to move all of your Auto-Response rules over to Workflow.

Please note that this KB article is provided as-is and customization using Workflow Rules is not supported.