Outlook.com and Outlook on the web can stop working if there is a service issue, if the account is blocked, or if storage is full.
First, check whether Outlook.com is experiencing an outage or service problem. Use the Outlook.com server status page to see if there are known issues affecting sign-in or mail access. If there is an outage, wait for the service to be restored.
If there is no outage reported and sign-in still fails on both computer and phone:
- Verify that the Microsoft cloud storage and mailbox are not full. If storage is full, sending and receiving email will stop until space is freed.
- If sign-in errors appear, use the Microsoft account sign-in helper to diagnose and fix account issues.
- If only certain devices are affected, remove the device partnership from the Outlook.com mailbox and re-add the account on those devices.
If problems persist after these checks, use the Outlook.com in-product Help or the Outlook.com support options to get further assistance.
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