Out of Office Assistant is a feature in Outlook made available when using Exchange. It can perform management of e-mail and auto-responses whilst you are away.
There are undoubted benefits of such a facility, yet also disadvantages that need to be understood before deciding whether to implement the facility.
The main things to consider are:
To Configure Out of Office Assistant:
In Outlook, select Tools from the Menu and select Out of Office Assistant
The following window will appear.

Select 'I am currently Out of The Office' and add an appropriate message in the Autoreply box below. This will now autoreply to every message you receive.
Should you wish to perform certain actions on messages, such as:
This facility can be achieved by clicking on the Add Rule button. The following screen will appear:

NB. Please bear in mind that the rule facility is further complicated due to the University operating two official e-mail addresses (@ncl.ac.uk, @newcastle.ac.uk). At present rules will have to be created with both. This is subject to change in the future.
Rules are applied from top to bottom in the Rule List, therefore messages that meet two or more rules may be affected by this.
To Remove the Out of Office Funtion:
From within Outlook simply go to Tools and Out of Office Assistant again and select 'I am currently in the Office'