Email to Case Premium supports the use of Lightning Email Templates, but the following step needs to be performed in order to make them visible for selection within the Email to Case Premium Setup Wizard.

In Salesforce's Setup, navigate to Lightning Email Templates and enable the Folders and Enhanced Sharing setting.



If you have already created a Lightning Email Template to use, we recommend you save it in a different folder other than Public or Private Email Templates. In the example below, a template was created in a Support folder, which can then be seen in the Setup Wizard for selection:



If you need a sample Lightning Email Template, Vicasso provides you with the following:



Use the following for easy copying/pasting:

Subject: {{{Case.Subject}}} {{{Case.Case_Thread_Id__c}}}

HTML Value: 
{{{Case.Most_Recent_Public_Comment_HTML__c}}}

{{{Case.HistoryText__c}}}

***************************

Case: {{{Case.CaseNumber}}}
Status: {{{Case.Status}}}
Priority Level: {{{Case.Priority}}}


{{{Case.Case_Thread_Id__c}}}

Note: This example is provided as-is and supporting custom email templates falls outside the scope of Vicasso's App Support agreement. If you need assistance with creating or editing custom email templates, please contact your internal Salesforce Admin or Salesforce Support.