Meeting Invites sent are not received by all recipients

Create a new meeting rather than restoring the cancelled one, send it first to one affected recipient, and have that recipient check Junk, the Other tab, and inbox rules; Microsoft does not currently document a general Outlook.com incident matching invitations being lost while cancellations arrive.^1^

Send a controlled replacement invitation

1. In Outlook.com, select Calendar → New event.
2. Re-enter the meeting details instead of editing or forwarding the cancelled event.
3. Add one affected recipient and send it.
4. Ask that recipient to check:
   • Inbox → Other
   • Junk Email
   • Filter → Sort → Date
   • Settings → Mail → Rules
   • Settings → Mail → Forwarding
   Outlook.com specifically identifies Junk filtering, inbox rules, forwarding, and message-list filtering as causes of apparently missing messages.^2^
5. If the test arrives, create or update the replacement meeting with the remaining recipients. If there are many attendees, add them in smaller batches so an affected address or recipient system can be isolated.

The cancellation reaching everyone does not recover the original invitation: it was a separate calendar message. The copy in Sent Items confirms that Outlook created and submitted the invitation, but the available information does not show where each recipient’s copy was filtered or rejected.

If the test invitation is still missing

• Check whether Outlook sends you a non-delivery report. Follow the specific error in that report:
  • Mailbox full/quota exceeded: the recipient must free space.
  • Blocked/listed/spam-filter error: the recipient’s email provider must review or unblock the sender.
  • Invalid address/domain: correct the address.
  • Timeout or message expired: wait briefly and resend.
  Microsoft documents these as receiving-server and filtering conditions rather than calendar-only failures.^3^
• If there is no non-delivery report, test an ordinary email to the same recipient.
  • If ordinary mail also fails, treat this as an Outlook.com mail-delivery issue.
  • If ordinary mail arrives but the new meeting invitation does not, retain the meeting subject, send time, recipient address, and time zone for support investigation.
• Check Microsoft’s service-status page for an active Outlook or Calendar incident.^4^

Escalate from Outlook.com

In Outlook.com, select Help, describe the issue, and complete the suggested troubleshooting. If it remains unresolved, scroll to Still need help? and select Yes. Microsoft identifies this as the support route for Outlook.com.^2^

Include:

• Approximate send time and time zone
• Meeting subject
• Number of recipients
• Whether recipients share one email provider/domain
• Whether a newly created one-recipient test invitation arrived
• Any non-delivery report or error text
• The fact that cancellation notices were delivered

References

1. Fixes or workarounds for recent issues on Outlook.com
2. Can't send or receive email in Outlook.com | Microsoft Support
3. Sent email in Outlook.com comes back "delivery failed" | Microsoft Support
4. Microsoft service health status