You can email a submitter from within the Submission Details page.
1. In the Submissions tab, click on the name of the submission sent by the submitter whom you'd like to email.
2. In the Submission Details page, click the Options menu in the upper right-hand side of the screen. Select Send Email.
3. In the Send Email dialog box, choose the email recipient in the Send to menu. To select multiple recipients, hold down the control key and click on multiple names.
4. Enter a Subject line and optionally choose a Response template from the drop down menu. Read more on Creating Response Templates.
5. If a response template is chosen, the email text area will be populated with the text for the chosen template. Otherwise, write your customized Email message.
6. Choose the Send from email address.
7. Click Send Email. The contents of the email will be logged into the Activity Feed column and also the account Activity log (under More > Activity).