Automatic Replies (OOF) enabled but it is not replying

I've enabled my Automatic Replies (Out of Office) and have sent myself a message from my private account to see how it would arrive. Sadly, I never received this automatic reply.

Why isn't it working and how can I make it work reliably?

Automatic Replies buttonWhen it comes to enabling the Automatic Replies (OOF) feature there are 3 things to note;

  1. By default, it doesn’t reply to people outside of your organization.
  2. It only replies once per address.
  3. It could get filtered out by Junk Email Filters.

In addition, note that it is an Exchange account feature. To get similar functionality for POP3 and IMAP accounts see this guide instead.

Automatic Replies doesn’t reply outside of the organization

Internal Emails buttonBy default, Exchange is configured not to send out Automatic Replies to addresses that are not within your company’s Exchange environment.

If you send yourself a message by using your Exchange account instead of your external private account (or ask your colleague to send you a test message), you should receive an Automatic Reply.

If it works now, you can ask your Exchange administrator to turn on the Automatic Replies feature on the Exchange server or to verify if it has been configured properly. A guide for this can be found here; Allow or prevent Automatic Forwarding/Replying to the Internet.

Automatic Replies - OOF - Outside My Organization - My Contacts only
When Automatic Replies to the Internet is allowed on Exchange, you can set it to reply to your contacts only to prevent replying to spam messages and unknown people.

Automatic Replies only replies once per address

From buttonOnce you’ve enabled Automatic Replies, it will only reply once per address. To have it send the message to all addresses again, you must turn off Automatic Replies and then turn it back on.

If you want to reply to each message that you receive, no matter how often that person has emailed you, you can emulate the Automatic Replies  function by a server-side rule similar as described here; Automatic Replies (OOF) with exceptions; Don't reply to everyone.

Note: For client-side rules, automatic replies initiated by a rule will still only reply once per address per Outlook session and Outlook needs to be running in order to process it.

Automatic Replies can be filtered out by Junk Email Filters

Junk Email buttonAs Automatic Replies are automated messages, they have a higher likelihood to get filtered out by Junk Email Filters. Especially various free providers tend to filter them out. If you are using a POP3 account, log on to your web based mailbox and see if it got delivered to the Junk E-mail folder there.

While you might be able to fix this for your own mailbox with your provider, there is nothing you can do to make sure it doesn’t happen for other receivers.

If you need to be a 100% certain that they get informed about your (extended) absence, contact them before you leave. Then if they would send you a message and receive your Automatic Reply, it would be more like a friendly reminder. You’ll probably receive less mail during your absence then as well and thus less to deal with when you return.

To pro-actively inform multiple people that you are away, you could use a Mail Merge.