Using New Outlook on Windows for professional communication and productivity
Hi,
Thank you for reaching out. I understand your concern regarding automatic replies not being sent despite being configured correctly.
Please try the following checks:
1/ Test from a brand-new sender address
Automatic replies are typically sent only once to each sender while the auto-reply feature remains enabled.
- If you've already tested using the same email address, that sender may not receive another automatic reply.
- To verify functionality, send a test message from a completely new email address that has not previously contacted the mailbox while automatic replies were enabled.
2/ Verify external reply settings
In Outlook on the web:
- Go to Settings > Account > Automatic replies.
- Confirm that Send automatic replies is turned on.
- If you're testing from an external account (such as Gmail, Yahoo, Outlook.com, or Hotmail), make sure Send replies outside your organization is enabled.
- If you selected Only send replies to contacts, external senders who are not saved in your contacts list will not receive automatic replies.
3/ Confirm the automatic reply message is populated
Make sure the automatic reply message fields are not blank.
- If the internal or external message box is empty, senders may not receive an automatic response.
For additional guidance, please refer to: Options > Automatic Replies | Microsoft Support
Recommended test: Configure automatic replies in Outlook on the web
Since you're using New Outlook for Windows, I recommend testing directly through Outlook on the web to rule out any client-side issues.
- Go to https://outlook.cloud.microsoft/
- Sign in with the affected business mailbox.
- Navigate to Settings > Account > Automatic replies.
- Turn automatic replies Off and save.
- Turn them On again.
- Enter both internal and external automatic reply messages.
- Select Send replies to anyone outside my organization.
- Save the changes.
- Test again from a sender address that has never been used for previous testing.
This helps determine whether the issue is related to the New Outlook client or the mailbox configuration itself.
If automatic replies still aren't working:
Please also check the following:
- Turn automatic replies off, save, wait a minute, then turn them back on.
- Remove any scheduling restrictions and set the reply to remain on continuously for testing.
- Review any Outlook or Outlook on the web rules that might be moving, redirecting, or deleting incoming messages.
- Confirm incoming test messages are reaching the Inbox and are not being quarantined or routed elsewhere.
- If this is a shared mailbox, verify that automatic replies are being configured on the shared mailbox itself rather than your personal mailbox.
Contact your IT admin :
If neither internal nor external senders receive automatic replies after completing the steps above, the issue may require administrative investigation.
Your IT administrator can review the mailbox configuration and, if necessary, open a support request through the Microsoft 365 Admin Center by following this guide: Get support - Microsoft 365 admin | Microsoft Learn .
If you’re unsure who your IT admin is, you can find guidance here: How do I find my Microsoft 365 admin? - Microsoft Support.
I hope this helps identify the cause. Please let me know the results of the Outlook on the web test, especially whether the issue affects both internal and external senders, and I'll be happy to help further.
Thank you for your patience and understanding.
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