Sending, receiving, and organizing email in Outlook on the web for business
For Outlook on the web, check these common causes in order:
- Check storage first. If Microsoft cloud storage or mailbox storage is full, email cannot be sent or received. Messages sent while storage was full can bounce back to the sender and are unrecoverable.
- Check whether mail is being filtered out of view.
- Open the Other tab if Focused Inbox is enabled.
- Check Junk Email, Deleted Items, Archive, and any custom folders.
- Make sure the message list is sorted by Filter > Sort > Date.
- Check Outlook.com settings that can redirect or hide mail.
- Review Rules for anything that moves or deletes messages.
- Check whether email forwarding is enabled.
- Review Junk Email settings and blocked senders.
- Check account access issues. If the password was changed recently, update it. The account can also be temporarily blocked because of unusual sign-in activity.
- If the problem is only on one device, remove the partnership between that mobile device and the mailbox to fix sync issues.
- If a specific message is missing, ask the sender whether they received a non-delivery report and have them review sender guidance.
For Exchange Online business mail flow, possible causes include spam filtering, quarantine due to a rule match, malware filtering, moderation, rejection by a rule or connector, delivery delays, or destination delivery failures. An admin can confirm this by running a message trace and checking whether the message status is Failed or Pending.
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