Sending, receiving, and organizing email in Outlook.com
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Hi, Dealers Choice
Since only one sender is affected, the message may be rejected before it reaches your mailbox. Another possibility is that your mailbox storage has reached its limit.
Here are some suggestions you can try:
Open Outlook.com in a browser, then select Settings > Account > Storage. Check both mailbox and Microsoft cloud storage. If either is full, new messages cannot be received, and messages sent while storage was full must be sent again.
Ask the sender to create a completely new test message, rather than replying to an old conversation. They should manually type your full email address and send the test without attachments or links. This helps rule out an outdated saved address or message content being rejected.
If you use a work or school account, ask your Microsoft 365 administrator to run the Troubleshoot Email Delivery diagnostic using both addresses. It can check whether the message was received, rejected, quarantined, or stopped by an organization-level mail policy.
If Outlook.com receives the test but the Outlook app does not, remove and reconnect the account in the app because this indicates a local synchronization issue.
Thank you for your patience in reading, I hope this information has been helpful to you.
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