By default, all emails sent from your account to your clients and staff are sent from service@casefox.com.  If you link your Google or Office365 account,  these emails are sent from your own Google or Office 365 account.  Alternatively, underInvoice/General Settings,you may also setup your own SMTP server.  Once successfully setup, invoices and emails from your account to your clients and staff will be sent through your SMTP server.