Open UT mailboxand log in to the mailbox with your university username and password (NB! @ut.ee must be added to the end of the username
Click on the gear-shaped button at the top of the page. In the menu that opens, click on View all Outlook settings, which you can find at the bottom of the menu.
In the opened window, click on Automatic replies. Turn on the auto-reply and set a message that suits you.
You can later turn off automatic notifications from the same place