Default Email-to-Case 'From' address for replies to email

A Salesforce User has the option of sending an email using one of the Routing addresses from the drop-down list in addition to the logged-in User's email address. 




In Salesforce Classic:
1- When sending a new outbound Email from the case record, the From address field  defaults to the logged-in user's email address

2- When Replying to an inbound message,

• With NO recipient in the TO field, the From address field auto-populates with the routing address to which the email was sent.  
• With 1 or more recipient in the TO field, the From address field auto-populates with the logged-in User's email address
• Note: If the Email-to-Case address is added on the CC field instead of the To field, the default email address when replying to the email will be the User's address and not the Email-to-Case Address.

3- When Forwarding an inbound message, (this is the exact opposite of the Replying to an email)

• With 1 recipient in the TO field, the From address field auto-populates with the routing address to which the email was sent.  
• With 2 or more recipient exist in the TO field, the From address field auto-populates with the logged-in User's email address

If Users want to use a specific FROM email address (such as an Email-to-Case address support@acme.com), they will manually select it from the FROM drop-down list.


In Lightning Experience:
1- When sending a new outbound Email from the Email-to-Case generated case record, the From address defaults to one of the Email-to-Case routing addresses. You can always use the drop down to select another routing address.

2- When Replying to an inbound message with 1 or more recipient in the TO field, the From address field auto-populates with the routing address to which the email was sent.  
Note: If the Email-to-Case address is added on the CC field instead of the To field, the default email address when replying to the email will be the User's address and not the Email-to-Case Address.

3- When Forwarding an inbound message,

If Users want to use a specific FROM email address, create a custom Email Action and set a Predefined Field value for the FROM field of the send email action. This will be the default FROM email address in the Case regardless on what FROM address is set in the previous email. In order to use this feature, keep in mind the user must click on Reply in the Case Feed to bring the Case Email composer in order to have the From address auto-filled according to the pre-defined field value in SendEmail quick action.



Review Set Predefined Field Values for Quick Action Fields