Open Outlook
Click the File tab
Select Automatic Replies (Out of Office)
Select Send automatic replies
Choose Only send during this time range (optional)
Set the start time and end time
In the Inside My Organization tab, type your out-of-office message
(Optional) In the Outside My Organization tab, check Auto-reply to people outside my organization
Type your external out-of-office message
Click OK to save and turn it on
To turn off early, return to Automatic Replies and select Do not send automatic replies