This is because configurations are set on the server, but you can still send an out-of-office message. If you're using an employer email account, then you might not be able to change settings for the Exchange server account. If you have an Exchange server configured, then this dropdown would show 'Exchange' below your email address.

In the image above, you can see that the account type is IMAP/SMTP because a Gmail email server has been configured with Outlook. You can find out if you have an Exchange account by clicking the 'File' tab and then clicking 'Info' in the left side panel. If you're an employee at an office that hosts its own email server and the organization uses Microsoft software, you might have an Exchange server as your email service. You can set up an Exchange server if you use Microsoft services such as Azure. Microsoft Exchange is an email server application available in network environments that use mainly the Microsoft operating system. We'll set up a non-Exchange message in the next section, but this section covers Exchange users. Native out-of-office messages using Outlook are only available to Microsoft Exchange users, but you can work with a non-Exchange account using rules. Outlook has a feature that lets you set these messages, which will be sent each time you receive a message in your inbox. The alternative is to create an out-of-office message that lets people know you're away.

Email never sleeps, so when you come back you could come back to dozens of senders angry that you never responded. You can't always be at your computer all day and night, and sometimes you leave for days either for vacation or because you're sick.

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