For a sudden stop in email after 2 days, start with the checks that most often block mail flow:
- Sign in to Outlook on the web and check whether new mail appears there.
- If mail appears on the web but not in the Outlook app, the issue is with the app connection.
- If mail does not appear on the web either, the issue is with the mailbox or mail delivery.
- Check mailbox storage.
- In Outlook.com, open Settings > General > Storage and confirm the mailbox or Microsoft cloud storage is not full.
- A full mailbox can stop new mail from being received.
- Check whether the account is blocked for verification or password issues.
- Try signing in to the Microsoft account in a browser.
- If prompted to verify identity or update the password, complete that step first.
- Check Outlook web settings that can redirect or hide mail.
- Review Settings > Mail > Rules
- Review Forwarding
- Review Junk email and blocked senders
- Also check Deleted Items, Archive, Other, and any custom folders.
- If sending is also failing in Outlook desktop, check the Outbox for a stuck message and make sure Work Offline is not enabled.
- Send a test message from another email account.
- If it does not arrive anywhere, and storage is available, the mailbox likely needs support-side investigation.
For speaking to a human support agent for Outlook.com mail delivery issues, use this path:
- Sign in to Outlook.com
- Select the Help icon in the upper-right corner
- Search for cannot receive emails
- Scroll to Still need help? and select Yes
- Choose Chat with a support agent in your web browser
- Confirm the request to create the service ticket
If the problem affects a custom domain mailbox, a DNS issue can also stop delivery.