Setting up a vacation message/Out of office auto reply
Log in to your Control Panel and select Mail administration.
Click Not active next to the email address you wish to add a vacation message for under the heading Vacation?.
Change Active? to Yes. In the Reply-To address field, type in the email address on which you want to receive replies of the vacation message.
In Subject type in the subject line you want for your vacation message. In the Message field, enter the vacation message and click Save to finish the setup.
The Reply-to Address field also can be explained as follows: When someone sends you an email, they will get your vacation message as the answer. If they respond to your vacation message by clicking Reply in their email program, their response will be sent to the email address you have specified as your Reply-to Address.
This may be useful for example if you are temporarily unable to check your professional mail, while still checking your personal mail. Then, set your personal email address as the Reply-to Address and enter a message like for example "If it is really important, please reply to this email, and I will get back to you as soon as possible."