With Exchange 2010, it is possible to set an Out of Office message for a user on the server side without resetting / asking for their password or accessing their mailbox.
To do so, access the Exchange Control Panel on a web browser using a URL as https://yourserver.yourdomain.com/ecp
Then follow the steps below:
- From Mail > Options, select Another User (default My Organization).
- Select the user you want to configure the auto-reply for. In the new window, ensure the user’s name is displayed in the alert message, and then click Tell people you’re on vacation. When managing another user in the ECP, an alert near the top of the page displays the name of the user you’re managing.
- From the Automatic Replies tab, configure the auto-reply options for the user.
A word of advise: The auto-reply messages will not be generated if the mailbox has an alternate recipient configured on the server and the Deliver messages to both recipient and alternate recipient option is not selected. In this scenario, the incoming message does not arrive in the recipients mailbox, and the Out Of Office Assistant is not initiated.