In this blog will see how to set Automatic Reply in Outlook (2013/2016) in Exchange Server.
Setting Automatic Reply in Outlook
Step 1: Open Outlook.
Step 2: Then click File tab in the top left of Outlook.

Step 3: Click Automatic Replies (Out of Office)

Setting Automatic Reply in Outlook Web App (OWA)
Step 1: Log in to OWA
Step 2: Then click Options (Gear Icon) in the top right

Step 3: Click Set Automatic Replies

Hope you succeed in applying automatic replies by following above steps.