Step 1: Sign into your Outlook webmail
Step 2: Click on Settings gear icon on the top-right corner.
Step 3: Scroll down and click View all Outlook settings
Step 4: Navigate to Mail >> Automatic replies.
Step 5: Enable Turn on Automatic replies option
Step 6: Click the Send replies only during a time period check box to specify time period for the auto replies
Step 7: Enter the response for inside and outside organizations in the respective fields.
Step 8: Click Save