This modification will allow you to email an order update notification ( manually ) to the client from within your store administration. An envelop icon is added to each order in your storeadmin ( below the SAVE button )
When processing your orders you would change the order status as needed, then click the envelope to automatically send an email with the new status notification info
The email they receive will be something like this:
Subject: "Your Site" Order Update
Your order status has been updated to [order status here] for order number [order number here ]. To view your entire order information online, please visit the link below:
[link provided directly to their order tracking status page]
IMPORTANT: Both Yahoo and AOL have updated their DMARC policies, and suggest using a domain email for web scripts. Please list ONLY a domain email address ( or gmail ) for the "Email address to send from"