If you know you will be unable to access your email for a few days or more, you may wish to set up an Auto-Responder. This feature is also commonly referred to as a "Vacation Auto-Reply".
An Auto-Responder is used to automatically reply to emails with a message you specify — so when somebody sends you an email while you are away, they will automatically receive your predefined response.
The Auto-Responder can be enabled and disabled at any time. While the Auto-Responder is enabled, recipients will only receive your automatic response once per day.