Sending, receiving, and organizing email in Outlook on the web for business
For Outlook on the web, start with these checks in Outlook.com / Outlook on the web:
- Check whether messages are landing in Other, Junk Email, Deleted Items, Archive, or any custom folders.
- In the message list, set Filter > Sort > Date to make sure messages are not just appearing out of order.
- Check whether email forwarding is enabled.
- Check whether any mail rules are moving, deleting, or redirecting external messages.
- Check Junk Email settings and blocked senders. If valid messages are in Junk, mark them as not junk.
- Check mailbox and Microsoft cloud storage. If storage is full, mail cannot be sent or received, and messages sent while storage was full are bounced back to the sender and are unrecoverable.
- If the account password was changed recently, update it. If the account was temporarily blocked because of unusual sign-in activity, unblock the Outlook.com account.
- Send a test message from an external account and check whether the sender receives a non-delivery report.
If only mail from outside the organization is affected, ask an affected sender to review Sender Support in Outlook.com. Microsoft notes that blocked sending IPs can be related to sender-side reputation issues such as namespace mining.
If these checks do not resolve it, use Help in Outlook on the web, search for the issue, then go to Still need help? and select Yes to reach support.