Microsoft 365 Email Not Working? Common Problems to Check

Microsoft 365 email not working? First identify whether the failure affects sign-in, sending, receiving or only one device. Record the affected account, exact error and start time before changing settings.

Use a labelled external test message to compare the desktop app with official webmail. Avoid deleting a profile or changing domain records until that comparison points to the affected layer. TempWebz provides IT and website technical support.

When Microsoft 365 email stops working, first identify whether the problem affects one user, one device or the entire domain. That distinction quickly reduces the number of possible causes.

Microsoft 365 email not working: test sign-in

Test the Microsoft 365 account in the browser. If webmail works but Outlook or a phone does not, focus on the device or application. If the account cannot sign in anywhere, check credentials, account status and licensing.

Sending versus receiving

Determine whether mail cannot be sent, cannot be received, or both. For domain-wide receiving problems, DNS and mail-routing records deserve attention. Recent DNS changes are especially relevant.

New Microsoft 365 setup

For a new domain, make sure the required Microsoft 365 DNS records have been added correctly and that old mail-routing records are not still directing messages elsewhere.

TempWebz provides Microsoft 365 setup and IT technical support for one-off email and configuration issues.

Microsoft 365 email not working: quick questions

What should I check first?

Start with the most recent change and the exact error or symptom. Check whether the issue affects every visitor, one device or one account before changing multiple settings.

Should I rebuild Outlook immediately?

Not as a first test. Check webmail, the account status and the exact desktop error. Preserve local-only messages, drafts and archives before removing an account or rebuilding a profile. A device reset will not fix a domain-wide mail-routing problem.

Can TempWebz investigate the problem?

Yes. Submit the issue through our technical support page with the website or service affected, the error message and any recent changes you know about.

Microsoft 365 email not working: getting further help

If the checks above do not resolve the problem, avoid making multiple unrelated changes at once. Record the symptoms and recent changes, then request technical support from TempWebz. For DNS-related failures, use our Microsoft 365 DNS guide. For a failure limited to Outlook, compare the checks in our receiving-mail guide.

Trace the failed message before changing policy

Ask the administrator to check the relevant delivery evidence, account status and any service incident. Record whether Microsoft 365 accepted the message, rejected it or placed it in quarantine. Do not disable protection across the organisation to test one uncertain email.

For outgoing authentication problems, Microsoft explains how SPF, DKIM and DMARC work together. Keep website forms and other third-party senders in the investigation because they may use a different route from staff email.

Verify the Microsoft 365 email repair

After a targeted correction, test fresh incoming mail, outgoing mail and a reply. Confirm the result in webmail and on the affected device. Check shared addresses separately where the business depends on them, and keep the cause and repair in the support record.