A user no longer manages to authenticate on Microsoft 365.
Probable causes
- Invalid password
- Account blocked or disabled
- MFA
- Conditional Access
- Licence or service incident
- User risk
Verifications.
- Test web connection — Use the Microsoft 365 portal.
- Control account in Entra ID — MFA status, licences and methods.
- View login logs — Remove code of failure and policy applied.
- Check service incidents — If more than one user is affected.
Solutions…
- Reset the authentication according to procedure
- Correct Conditional Access Policy if it is in issue
- Re-establish license or account if necessary