If you use Google Mail and you have deleted email permanently, by hitting 'Delete Forever' in your Trash or Spam folder, you can not recover the email using the Google mail interface.
But if you just have moved email to Trash folder, using 'Delete' button, but it has been less than thirty days and you have not permanently deleted the email, do the steps below to put email back to your inbox:
1. Sign in to your Gmail/Google mail account.
2. Click 'Trash' tab on lef side bar.
3. Choose the message you would want to move back to inbox, and thick the box by the email.
4. Click 'Inbox'.