Hi @Liam Oosthuizen
Welcome to our forum!
Here are some steps you may take:
For Individual Users:
- File>Automatic Replies>Select Send automatic replies>Set the start and end times for the automatic replies. Note: Please enter your message for both internal and external senders.
For the Entire Company:
- Sign in to the Microsoft 365 admin portal by using administrator credentials.
- Expand Admin Centers, and then select Exchange.
- Under Recipients > Mailboxes, select the mailbox that you want to change.
- Select Others, and then select Manage automatic replies under Automatic replies.
More information: How to set automatic replies on a user's mailbox in Microsoft 365 - Exchange | Microsoft Learn
However, if you want to automatically turn on automatic replies at a fixed time every day, you may have to turn it on manually or use a script. Please kindly understand that the Outlook tag here we mainly focus on general issues about Outlook desktop client, it is recommended that you consult your company's IT for details code.
Hope it helps!
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